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Know a little something about maintenance, fixing, tuning, or modifying MX, offroad, & dual sport motorcycles, ATV or UTV? Or, maybe you have mad skills riding or racing them? Whatever the case, if you have valuable knowledge & experiences that relates to motorcycles, ATVs, or UTVs, please help your fellow riders by sharing your best tips, tricks, and how to articles.

    Freemotion
    I need to win. I have to win. It is an ever-present mindset in everything I do, but especially racing dirtbikes. In order to accomplish this I have to be constantly pushing, striving to get better. Spending most of my seat time on the ragged edge of control and out-of-control means I spend a decent amount of time in the dirt, and spent a whole lot more time there when I was learning to ride a 300 two-stroke this past year.
    My 2018 KTM 300 XC-W Six Days was the first new vehicle I've ever had of any sort. Because this bike meant a lot to me, and I could not afford a new pipe every ride, I went looking for protection, for armor.
                
    *A Mykel Horner Photo
    I came across an Emperor Racing skid plate and pipe-guard combo at a distributor and new instantly it was what I needed on my bike if I was going to keep it Ready to Race. Before I could purchase it, it was purchased at retail for me for Christmas by my girlfriend.
    I had no idea the history and passion behind Emperor Racing until I moved to Colorado and started racing for Emperor Racing as a fully supported rider. I already knew the products were awesome and racing under Emperor I got to work with Steve and really get to know the Canadian company.
                                           
    At the Helm, a Mechanical Designer by trade, rider by blood; Steve Vander Helm, proud Canadian. Talk about passion for our sport. Rider through and through, and has the professional skills to conceptualize, develop, and produce some premier dirtbike protection parts.
                  
     
    They machine very high-grade, high tolerance type pieces to not only look killer, but perform even better. Steve started doing mechanical design for the elevator industry and later for the heavy steel industry designing dump truck boxes, low bed heavy-haul trailers and precision excavator attachments. From there he designed parts for most of the elevators you see and use today. He saw the successes of his designs and the company owning patents of his design, but never saw the value returned to him as the designer. Eventually Steve concluded that he was better off solo. But what would he design? Steve was then, and is now, an avid rider. He noticed these riders all getting new bikes but could not get guarding products for them in a timely manner. From there; the idea of Scorpion Racing is born. 
    Steve figured he spends all his time riding and racing, saw the demand for the product at his races and knew he had the skills to bring it to life. So he decided to start a company called Scorpion Racing that made premium, rock-solid dirt bike parts because he was already making custom plates for all his buds, but custom-only was not going to be profitable at scale so he started producing the first generation light skid models in 2005. Soon after that was the 1st gen rad Rad guard.
                                             
                   2007 Model Lightweight Guard for WR450
    Fast forward to 2008, the market needs a heavy duty model. Riders have been asking and Steve had been prototyping some models and releases the Heavy Duty Skid Guard combo, under the Scorpion Racing name, that is the root of his flagship product today.
                                               
                 *2008 HD Skid Plate for KTM & Husky 
    In 2012, Pirelli tires forced then Scorpion Racing off their name citing they already had that brand established. They then re-branded as Emperor Racing as it became a situation where whoever had the most money to throw at lawyers was going to win that one. Steve made the smart business decision to not take on the tire giant as he was out-gunned.
    Ever since Steve’s inception as Scorpion Racing back in 2005 his products have always been created through extreme testing and rider input. He takes that feedback and uses that mold his next models or improvements. That’s huge. And I think lost on a lot of companies nowadays. Most other companies are so full steam ahead with their vision they might have stopped to consider the consumer’s needs.
    The flagship product today, the Pipe Guard Skid Plate is a beautiful piece of machining. Start to finish, end to end, you can tell it’s something made by someone with a lot of pride in what they do. Beveled edges, high-grad Alu, all metric hardware, the list goes on. The quality and craftsmanship is very obvious with handling these plates. On the bike is even better. Being all aluminum they have a UHMW plastic "Slip Liner/ Link Guard" easily bolted to the plate that does exactly what the name suggests; help you skate over obstacles easily and protect your linkage, win-win.
    *These products are available for most recent & current model year 250 & 300 two-strokes, and the 250, 350, 450 model four-strokes

    This plate is the real deal. I can now practice here in The Rockies with confidence. Bashing rocks and logs 10 miles away from the truck down some gnarly single-track can lead to some stranded-type issues if things go sideways. I think broken clutch covers, crushed stator, mechanical DNF’s, etc. are all severely reduced, if not eliminated altogether by having this grade of protection.
    It mounts firmly to frame with a secondary plate/bracket that stops the force of impacts from being transferred to the exhaust. Snug-fit hardware throughout makes install super easy. No holding bolts in place while trying to find them with a bolt. Oil changes can be done without removing the plate.
    The rad guard of today morphed from a Scorpion two-piece design to a one-piece, brace & guard that protects the radiators very well. The biggest issues with a rad guard are the limits riders want: We do not want a width increase, height increase, want to be able to mount aftermarket fans, nothing on the back, easy mounting, light. The Emperor Rad Guard does all that. I have use it and crashed with it plenty. It does its job.
               
     
    A product’s warranty is a great way to gauge how the company feels about their product, especially those that make wear parts. Steve offers a 1 year warranty on his products and stands by that warranty. I know, I've tested it. 
    I had some riding buds in town soon after moving to Colorado. We went for a ride on some trails that were new to all of us- that’s always fun- new trail. We were moving through some double-track on the lookout for a trail. I was leading and came up to a Y in the road about 35-40mph. I was slightly entering the left-hand trail when noticed we needed to go right. So I pulled across the grass ‘median’ and caught a rock hiding in the grass.
    The plate acted as a crumple zone and transferred the impact through my pipe and bent it at the weakest point, the joint. I was able to ride the rest of the day without limitation.
           
    I had to cover shipping both ways but Steve replaced the guard at no charge and replaced a brand new guard for the cost of shipping. I am only the 2nd person that needed a plate warrantied. It was an easy process and hope to not need to warranty another.
    The story here is a cool one. A very smart and production-capable rider started making great products 13 years ago. His love for the sport makes him constantly striving to innovate and stay on top of what the consumer wants in premium bike protection. I think its some of the best money spent as I would surely have cracked cases, an exhaust flange, something by now learning splat and crossing techniques for racing enduro.
                                             
    People often see the skid plate and rule it out for weight or frame flex reasons. It weighs 7lbs and the weight is sprung. I think you have to ride at a pro or season pro level to feel stuff like that, but perhaps not. For me it’s saved my race, my day, my bike. Until I manage to stay off the ground and clear obstacles I’ll likely be riding with Emperor Protection.
    If you’re interested in protecting your bike and getting that peace of mind I would encourage you to look to at EmperorRacing.com. They are in full support of our sport, put their money where their mouth is, rider founded, rider ran and they make some damn good products and I am proud to ride for them.

    We will be doing write up and review on the skid plate and the rad guard separately. Long ago, when installing the first skid plate on my bike I decided to write up a how-to to do the install. If you need any more help you can refer to that walk-through here.
     
    Bryan Bosch
    Every industry has iconic brands that pretty much everyone knows about. If you ask a rider to name a leading dirt bike exhaust brand, they’ll likely say FMF. Ask the same about handlebars and you’ll probably hear Renthal or Pro Taper.
    I also encounter brands that make really good stuff, but for any number of reasons, just aren't well known. One such brand is USWE Sports, a Swedish manufacturer of high-quality, high-performance hydration packs for the moto, mtb, snow, and running sports. Interestingly enough, you just might have experienced a USWE product, as they made packs for popular moto brands such as Leatt, MSR, and Fly Racing. 


    Action Pack, NOT Backpack!
    So, what's the "secret sauce" that USWE bakes into its action packs that makes them especially good for us dirt bike guys? At the heart of USWE hydration packs is NDM (No Dancing Monkey 🐵) technology. It’s a goofy visual for their award winning, patented 4-point suspension harness and buckle system that allows the pack to form fit very snug against your body, virtually stopping pack bounce in rough terrain, while maintaining comfort, freedom-of-movement & breathing capacity. This sounds like a simple enough task, but it’s taken many iterations and thousands of sweaty riding hours to get USWE action packs to this level of performance. Even the bladder itself has design elements that work in concert with their patented harness to minimize and control pack movement. Here's a short video that demonstrates NDM tech (harness demo @ 1:12).
     
    From the Swedish Horse's Mouth
    Recently I caught up with Karl-Johan Engdahl, USWE Co-Founder and Business Development & Marketing Director for a few questions:
    TT: The USWE name... What’s the backstory there? Something interesting in Swedish?
    TT: USWE has been in the hydration pack game for over a decade. What accomplishment are you guys most proud of?
    TT: Amazing riders like Colton Haaker, Cody Webb, Taylor Robert, Billy Bolt, and Alfredo Gomez are USWE sponsored. How much of a role do they play in shaping USWE product development and design?
    TT: At least in the US, you can walk into most big box stores and pick up a hydration pack for pretty cheap. Why are some riders still spending more money on USWE hydration packs?
    TT: Where can we expect to see USWE this year in terms of events & series?
    TT: The floor is yours Karl. What else do you want riders to know about USWE and its products?


    USWE Athlete, Billy Bolt @billybolt57
    USWE wants to get their action packs in the hands of riders because they're confident that once tried, they'll be a convert. Stay tuned for a USWE product giveaway that we'll be hosting before the end of the year. They'll be giving away a bunch of action packs to lucky Thumpertalk Community Members! Maybe you'll be one of them? 🤞
     
    USWE 2019 Action Pack Line-Up
    NDM HARNESS - INCL. IN ALL USWE ACTION PACKS (EX. H1)
    Race Suspension - NDMTM patented technology 4-point stretch harness that supports max breathing capacity and freedom to move Solo-buckle secure system makes it easy to take on/off the pack even while wearing gloves Ergonomic shoulder and chest straps with dual-loop Velcro multi size function 100% bounce free in action
      ZULO HIPBELT SERIES - NEW
    Available on-line end of October. In stores sometime December 2018.


    ZULO 2
    SUPERLIGHT RACE HYDRATION HIPBELT
    1.0L/35oz Hydrapak EliteTM hydration bladder Magnet tube clip 2L total cargo capacity Organizer pocket: keeps your tools and gear in safe position Size: Multi size adjustable: S-XL, Adult Light mesh back panel LED-light attachment points: Front and back Colors: Carbon Black, Crazy Yellow ZULO 4
    Will be announced soon..
     
    OUTLANDER PACK SERIES
    NEW! Available ONLINE end of October. In STORES during December 2018. Will be our Moto head product. Single color options.

    OUTLANDER 2
    SUPERLIGHT RACE HYDRATION PACK
    1.5L/50oz Hydrapak EliteTM hydration bladder 2L total cargo capacity Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 38cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult High-ventilated shoulder straps with foam pads Light mesh back panel LED-light attachment points: Front and back Brace compatible Colors: Carbon Black, Crazy Yellow
     
    OUTLANDER 3
    RACE HYDRATION PACK W. ON/OFF ORGANIZER
    1.5L/50oz Hydrapak EliteTM hydration bladder 2 + 1L (3L) total cargo capacity On/Off organizer pocket Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 38cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult High-ventilated shoulder straps with foam pads Light mesh back panel LED-light attachment points: Front and back Brace compatible Colors: Carbon Black, Crazy Yellow OUTLANDER 4
    HARD ENDURO HYDRATION PACK W. LARGE HYDRATION CAP.
    2,5L/85oz Hydrapak Shape-ShiftTM hydration bladder (open baffle 3,0L/100oz) w. Plag-n-Play 4L total cargo capacity Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 38cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult High-ventilated shoulder straps with foam pads Light mesh back panel Brace compatible Colors: Carbon Black, Crazy Yellow OUTLANDER 9
    ADVENTURE HYDRATION PACK W. LARGE HYDRATION CAP.
    3,0L/100oz Hydrapak EliteTM hydration bladder Bladder compression sleeve: keeps bladder in fixed position 9L total cargo capacity Organizer pocket: keeps your tools and gear in safe position Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 45cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult High-ventilated shoulder straps with foam pads Light mesh back panel Brace compatible Colors: Carbon Black, Crazy Yellow
      RANGER PACK SERIES
    Available NOW
    RANGER 3
    RACE HYDRATION PACK W. ON/OFF ORGANIZER
    1.5L/50oz Hydrapak EliteTM hydration bladder w. Plug-n-Play 2 + 1L (3L) total cargo capacity On/Off organizer pocket Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 38cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult Light mesh back panel Brace compatible Colors: Black/Black, Orange/Black, Blue/Black RANGER 4
    HARD ENDURO HYDRATION PACK W. LARGE HYDRATION CAP. 2,5L/85oz Hydrapak Shape-ShiftTM hydration bladder (open baffle 3,0L/100oz) w. Plug-n-Play 4L total cargo capacity Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 38cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult Light mesh back panel Brace compatible Colors: Black/Black, Orange/Black, Blue/Black
    Giving the USWE Ranger 9 a shot - Withlacoochee National Forest, FL
     
    RANGER 9
    ADVENTURE HYDRATION PACK W. LARGE HYDRATION CAP.
    2,5L/85oz Hydrapak EliteTM hydration bladder w. Plug-n-Play Bladder compression sleeve: keeps bladder in fixed position 9L total cargo capacity Organizer pocket: keeps your tools and gear in safe position Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 45cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult Light mesh back panel Brace compatible Colors: Black/Black, Orange/Black, Blue/Black
      PATRIOT 9L PACK
    Available NOW


     
    PATRIOT 9
    ADVENTURE HYDRATION PACK W. LARGE HYDRATION CAP., QUICK STASH
    POCKET & ARMOR ATTACHMENT
    2,5L/85oz Hydrapak Shape-ShiftTM hydration bladder (open baffle 3,0L/100oz) w. Plug-n-Play Bladder compression sleeve: keeps bladder in fixed position 9L total cargo capacity Organizer pocket: keeps your tools and gear in safe position Quick stash pocket and attachment points for gear Water resistant media pocket (W 8.5cm x D 16cm) Dim: H: 45cm x W: 29cm x 8 cm Size: Multi size adjustable: M-XL, Adult Light mesh back panel Brace compatible Colors: Camo, Chili Red
      TANKER 16L PACK
    Available NOW

     
    TANKER 16
    ADVENTURE PACK – HYDRATION COMPATIBLE
    ▪ Hydration compatible
    ▪ 16L total cargo capacity
    ▪ Organizer pocket: keeps your tools and gear in safe position
    ▪ Water resistant media pocket (W 8.5cm x D 16cm)
    ▪ Dim: H: 50cm x W: 29cm x 8 cm
    ▪ Size: Multi size adjustable: M-XL, Adult
    ▪ Light mesh back panel
    ▪ Brace compatible
    ▪ Colors: Black/Black, Orange/Black, Blue/Black


    XC PACK SERIES
    Available NOW

     

    XC ELITE
    LIGHT HYDRATION PACK
    ▪ 1.5L/50oz Hydrapak EliteTM hydration bladder
    ▪ 2L total cargo capacity
    ▪ Dim: H: 38cm x W: 29cm x 8 cm
    ▪ Size: Multi size adjustable: M-XL, Adult
    ▪ Light mesh back panel
    ▪ Brace compatible
    ▪ Colors: Black/Red
    XC / XC JUNIOR
    LIGHT HYDRATION PACK W. DISPOSABLE HYDRATION BLADDERS
    ▪ 1.5L/50oz Disposable hydration bladder
    ▪ 2L total cargo capacity
    ▪ Dim: H: 38cm x W: 29cm x 8 cm
    ▪ Size: Multi size adjustable: M-XL, Adult
    ▪ Light mesh back panel
    ▪ Brace compatible
    ▪ Colors: Black/Red


    H1 RACE HARNESS
    Available NOW


     
    H1 RACE HARNESS
    SUPERLIGHT HYDRATION HARNESS (MX & ENDURO)
    ▪ 0.5L/18oz Disposable hydration bladder
    ▪ Size: Multi size adjustable: M-XL, Adult
    ▪ Full-mesh body for optimal weight and ventilation
    ▪ Velcro stretch straps that supports max breathing capacity and freedom to move
    ▪ NOT brace compatible
    ▪ Colors: Black/Red
     
    You can learn more about USWE Action Packs HERE.



    Bryan Bosch
    Updated 09/25/2018
    Recently, American Honda invited me out to Packwood, Washington to ride the 2019 CRF450L, one of the most hotly anticipated new motorcycle model releases in recent memory. I’ve been reading posts for years from riders begging the Japanese manufacturers to bring them a modern, performance oriented dual sport motorcycle, and I too was happy when I learned that Honda had stepped up. Increased competition means better bikes and more choices for us riders! 
    Despite our stickers all around, Honda didn't let me keep this 450L .
    Our 106 mile test loop included a section of country highway, twisting back roads, gravel forest service roads, fast & flowing double track, and epic technical single track. Weather was cool & damp and we rode elevations from approximately 1,000 to 5,300ft.

    106 Miles of Dual Sport happiness!
    Our test bikes were stock except for the installation of Dunlop D606 DOT tires, suspension clicker adjustments for the conditions being ridden, and sag adjustment as necessary. I’m a 49 year old, off-road focused dual sport rider with 35+ years of recreational riding experience. I’m not always the fastest in the group, but I rarely bring up the back either.
    What Type of Rider is the CRF450L Most Suited To?
    I think Honda was pretty accurate by framing the 450L as a trail-to-trail, performance dual sport. No question that it leans more towards the true dirt side of the spectrum, but with enough comfort and refinement baked in to make your ride to the trailhead and connecting trails enjoyable. It’s docile enough for a developing rider with decent throttle & clutch skills to enjoy on mild to moderate single track, but still has the ability to satisfy accomplished riders who like to push in more demanding conditions. Our test group included a few very fast riders (including Johnny Campbell) and no one said that the bike was holding them back much, if at all. I certainly didn’t feel limited when pushing anywhere. What the 450L is not is a light-duty trail machine designed more for traveling distance on graded dirt roads or highway. It very well might just do that, but it certainly isn’t one of its core competencies, nor would it be my first choice for such. 
    Does the CRF450L Have More Than the Rumored 25hp?
    Oh, heck ya! Honda didn’t provide actual dyno numbers, but they estimated the 450L to be in the mid 40hp range. My butt dyno says that’s in the ballpark. It has enough oomph to keep things exciting, but not so much that you can get in trouble quickly when you're tired. No question that fire-breathing power can be fun, but for a long day in the saddle, the 450L power didn’t unnecessarily wear me out.

    Yeah, the CRF450L will wheelie. Photo by Drew Ruiz
    Throttle response is crisp and power delivery is super smooth & completely linear to its 10,000 rpm redline (5th gear). Roll-on power lower in the RPM range is initially a tad soft, something fairly common with emission controlled dual sports. However, a downshift or handful of clutch produces pretty much instant boost. To be fair, I’m a bit of a short shifter, so riding the bike in lower gear at a little higher RPM kept the motor in the sweet spot of the power curve.
    The 450L has a 12% heavier crank and a heavier clutch basket than the 2019 CRF450R, making the power very tractable and resistant to stalling. The 450L put the power down incredibly well, making for excellent traction despite running a little higher tire pressure than I prefer (15psi front & back). I did manage to stall the bike a few times, but I blame that more on my left hand and gear selection than the bike.
    I asked Honda if the ECU could be remapped, but they were a little hesitant to dive into that pool. And, I understand why. I pressed them just a bit and they did say that the ECU can compensate to some degree, such as for an aftermarket exhaust and that an ECU remap may be possible. You’ll have to form your own conclusions.
    Is the CRF450L Showa Suspension Any Good?
    The 2019 CRF450L has the same, fully-adjustable Showa 49mm coil spring fork & Pro-link shock as its 450R & 450X cousins, but specifically tuned for performance dual sport riding. It’s sprung for around an 180lb. rider (fully geared) and Honda took into consideration that some riders will be adding additional weight with the installation of a rack or soft luggage and cargo. Since we're talking about cargo, the aluminium sub-frame extends the full length of the rear fender and while Honda didn't quote us a weight limit, I rode at least a 175lb. rider back to his bike. I suspect that it will handle pretty much whatever most riders will need to carry.
    Fully geared up, including a full hydration bladder and trail incidentals, I’m right at 210lbs.. Despite being 30lbs. over the ideal spring weight, I thought that the 450L suspension worked incredibly well. Riding over washboard forest service roads at a pretty good clip, I took note of how planted and composed the bike remained. On the trails it soaked up rocks and roots well, and even square edged hits didn’t transmit harshly though the handlebars or upset the chassis. I also took note of how well the bike handled sections of stutter bumps, something that does a good job of exposing suspension weaknesses.

    Fun fast & flowing section of Pac NW single track. Photo by Drew Ruiz
    On one of the higher-speed dirt roads, climbing up to a decommissioned fire outlook (Burley Mountain) were some awesome roller humps. I didn’t slow down for one in particular and when I was just about to lift off, I noticed that I was going to land in a dip on the other side. I figured that I was going to bottom out both ends, but to my surprise, the suspension fully soaked up the hit! Suffice to say, out-of-the box, I think that the 450L Showa suspension is highly effective, forgiving, and can only get better if sprung and valved for a rider’s weight, conditions, and skill level.
    Does the CRF450L Feel Heavy?
    I guess that depends upon what you’re use to. It feels noticeably lighter than my KTM 690 Enduro R, but not too much heavier than a KTM 450 EXC that I used to own or a KTM 450 XC-W that I rode this summer while in Colorado. Nowhere on the trail did I feel like I was wrestling a beast or fighting against the bike.
    The 450L has a slightly longer wheelbase than the 450X for added stability on the road, but it still dropped into turns willingly and steered accurately. It didn’t take long for me to build confidence in the bike’s handling, trusting the front-end to stick and to start brake sliding into corners. The 450L is a very predictable handler, confidence inspiring, and fun to ride. I don't think it took more than an hour on the bike to feel right at home.
    For those looking to save every ounce of weight, the biggest savings will probably come from an aftermarket exhaust, as the stainless silencer includes a catalytic converter to comply with emissions. It already comes with a light-weight Lithium battery, so there simply isn’t unnecessary weight just hanging around. Me? I wouldn't touch the stock exhaust and I'll cover why later in my review.
    How’s the Gas Mileage?
    The specs have been out on the 2019 CRF450L for a while now, so many have already shared their concerns about its 2 gallon fuel capacity. Obviously, mpg is going to vary by how you ride the bike and the conditions being ridden. Honda quoted an average mpg for mixed conditions of 50, so right at 100 miles per tank. While the digital dashboard doesn’t have a traditional fuel gauge that displays what you have left, it does tell you how much fuel you’ve consumed, how far you’ve ridden, and your average mpg for both trip A and trip B settings.
    Admittedly, when we got back from the ride, I was pretty tired, soaked to the undies, and ready for a hot shower. So, I forgot to check how much fuel the bike had burned!  What I do know is that approximately 2 gallons took me through 106 miles of epic Pac NW mountain roads & trails, I didn’t ride with fuel economy in mind, and I absolutely got my fill of riding that day.
    For some riders, 2 gallons won’t be enough, so they’ll have to look to the aftermarket for a solution. I recently talked to Chris Harden, the GM at IMS Products and he confirmed that they’ll have an extra capacity tank ready in about 6 weeks. He further said that it should be between 3 to 3.2 gallons in capacity, have a screw cap and dry break option, and colors of black and natural. IMS will be sending me a 450L  tank to check out, so I’ll post up some pictures when it arrives. Curious to see where they found the extra room.
    How’s the Gear Box & Clutch?
    The 2019 CRF450L features a 6 speed wide-ratio transmission with fairly low 1st gear for tight conditions and a 6th with enough legs for highway speeds.
    1st gear is usable in very slow, technical conditions, but the bike can feel a little jumpy at times because the fuel mapping is somewhat sensitive. If you have good throttle and clutch control it’s not a big deal, it's just something that I noticed while getting to know the bike. In terms of gear spacing, I think Honda did a good job with the ratios, not noticing any unexpected or annoying gaps.
    I was able to get the 450L up to 80 mph on a longer back road (closed for safety of course ) and there was still more speed to be had. I don’t see an issue with the bike cruising at 65-70, 75ish for shorter runs, and 80-85ish when passing. The 450L doesn't have a tachometer, so I can’t say what the bike was turning at different speeds. But for the vast majority of traveling speeds, the bike isn't rapping out or feeling like you’re squeezing. I asked Honda for the 450L transmission gear ratios, but I'm still waiting on them. I'll add them here when they come in. Honda did say that at 65 mph, the engine is turning in the 6,000 rpm range.  ****Updated 09/25/18: Actual Gear Ratios***
    Overall, I really enjoyed the 450L gearbox.  It’s very smooth to operate, it’s quiet, and despite being on an unfamiliar bike, I didn’t have a mis-shift the entire day. I wish my 690 transmission was this good honestly. As a point of reference, I wear size 10 boots and getting under the shift lever was no problem.
    I was initially a little disappointed to see that the 450L doesn't have a hydraulic clutch, but I found lever pull to be smooth and light as far as cables go. The clutch perch has a manual adjuster wheel that works well, even with gloves on. We didn't ride hard enduro conditions, but there were sections of technical single track that required more aggressive clutching and I didn't notice any fading or chatter.  Both control levers are on the shorty side, something I prefer and both were effective with two fingers.
    How are the CRF450L Brakes?
    The 450L has a 260mm cross-drilled wave rotor up front that is squeezed by a Nissan 2-piston caliper. To meet DOT requirements, the front rotor is a thicker and the hydraulic reservoir carries more fluid. At the rear is a matching 240mm rotor and single piston caliper. No ABS is present at either end.
    The front brake has good initial bite without being too grabby. I found it easy to modulate, fade free, and plenty powerful. The back brake was a little grabby, but I was just using it how I ride my 690. Once I adjusted my inputs it was fine and in short order I was brake sliding into corners like normal. The brakes were also able to haul the bike down from 70-80 mph on wet back roads with no drama.
    Is the Seat Comfy?   
    It’s a slim profile dirt bike seat with fairly firm foam that, for its intended purpose, it's fine. Compared to the range of MX and Enduro bikes that I've ridden, it's one of the more comfortable, but it's not XR650L comfortable for example. Surprisingly, I didn’t start to get uncomfortable until the last hour, hour and a half of the day, but we also rode a decent amount of stand-up terrain. I’m sure that the aftermarket will bring 450L comfort oriented seats to the market very soon. I did like the seat cover; it has good grip, even when riding in wet conditions.
    Is the CRF450L Tall?
    At 5’ 10” with a 32” inseam, I’m pretty close to reaching the ground with both feet flat. Considering all the different dirt bikes, dual sports, and ADV bikes that I’ve ridden, no, I don’t think that 450L is tall. It has the same amount of suspension travel as the CRF450R and X, but it’s a little heavier, so it sits slightly lower in the stroke.
    For the first couple of road miles, I thought that the seat to peg room was going to feel a bit cramped, but that thought quickly disappeared as the miles increased. One thing that I did like was how the textured radiator shrouds give you more traction at the knees and their profile created the perfect "pocket" when scooching up on the tank for sit down corners. If Honda made the textured areas of the radiator shrouds out of a little softer (grippier) material, they'd be even better.
    Are the Service Intervals Reasonable?
    For 2019 CRF450L, Honda specifies 600 mile oil change intervals and 1,800 mile valve checks. For the intended purpose of this bike, I don't think that's unreasonable. For oil, that's a half a dozen rides just like our test loop and 18 of the same for valves. At least for me, that's a lot of run relative to the time and maintenance costs. And, Honda is known to be conservative with their recommendations, so personally I wouldn't sweat going 10-15% over those miles occasionally. 2019 CRF450L service interval matrix
    In terms of long-term reliability, there's no way I can tell you from a one day ride. The best indicators will be how later gen 450X models have held up and to a lesser extent, the 450R. Few would argue that Honda doesn't have a reputation for quality and the warranty on the 2019 CRF450L seems to back that up. It comes with a 1 year factory warranty, but the same can be extended out to 5 years total for an additional cost. You can even buy just an extra year or an extra 3, so flexibility has been built into the program. I do know that the 450L uses a 3-ring piston that will extend top-end life at a fractional performance cost pretty much no riders will notice. This just makes sense for the application.

    Illustration: American Honda
    Is the LED Headlight Effective?
    We didn’t get an opportunity to night ride, so we improvised and pushed a 450L into a field on the edge the hotel, pointing the headlight into the woods.

    The cutoff height increases with a rider on the bike. Pics taken with no rider. Photo by El Jefe of CDSR.
    I think that the CRF450L headlight would do a good job for a night time cruise on back roads at legal-ish speeds and no question that it would get you off the trails if you got caught out after dark. But if you really want to trail ride at night, get something helmet mounted.
    Anything That I Didn't Like About the 2019 CRF450L?
    The clutch lever perch has an internal switch that requires the lever to be pulled fully against the grip in order to restart the bike. It wasn't a huge deal for me, but something that I noticed when I flamed out and tried to get the bike lit quickly with the magic button. I know that this was a point of feedback from some of the very fast riders in our group to Honda engineers who eagerly solicited feedback after the ride. 
    I also don't like that there is no back-up kickstarter for a dual sport that is designed to get deep into the woods. I did confirm with Honda that the new engine cases do not allow for one to be installed retro.  My KTM 690 shares the same design and in the last 1.5 years of ownership it's been no issue. Honda has a pretty solid reputation for reliability, so I think that this falls under the premise that all things are possible, but not all things are likely. For those that Murphy's Law seems to follow, there are good portable jump starters that are easily carried in small packs and "smart" batteries that protect themselves from over-discharge such as the Antigravity "Re-Start"  Lithium battery.
    At least for me, the horn button is too easy to hit when you're looking for the turn signal switch. The button is above and sticks out past the signal switch below it, so I ended up honking at the rider in front of me a few times accidentally. But, by the end of the day, I had adapted. The turn signal switch gets used far more than the horn, so I think there's room for improvement ergonomically.
    What Really Stood Out About the CRF450L? 
    Probably how smooth, refined, and quiet this bike is, despite it being so performance oriented and capable. The combination of rubber dampened sprockets, chain guide, roller & slider materials, urethane filled swingarm, and foam-backed plastic ignition, clutch, and primary sprocket covers help to make this the most refined, low vibration, and quiet street legal dirt bike that I've ridden. Add in a quiet exhaust note and the 450L is pretty stealthy. After a full day of riding, I had a ton of fun, never felt held back, but I really appreciated the lack of mental & physical wear that loud and more raw bikes have. Loud pipes don't save lives, but they do tick off others recreating in or living by the areas we ride.

    Quiet, refined, & stealthy doesn't have to kill the thrill. Photos: American Honda
    Honorable mention: The LED turn signals double as running lights and can be bent 90°, snapping back into operating position without damage. It's a little detail, but a smart and appreciated one. On a bike like this, conventional signals on the rear would last days if not hours.
    Would I Personally Buy a 2019 CRF450L? 
    Absolutely. Since I left the event, I've been thinking hard about putting a 450L in my garage. I really like this bike a lot. I've not been on a Honda since mid 2000 and they brought their guns to the performance dual sport market with the 2019 CRF450L. Glad to see Honda shaking up the segment and riders are the winners. I wonder who will fire back next? 
    Questions & Comments?
    I could probably write more about the 2019 CRF450L, but I think that I covered the important stuff and the things that stood out to me. But, the cool thing about ThumperTalk is the conversation. If I didn't do a good job explaining something or worse, completely glossed over something important to you, DO post your question(s) in the comments section below. If I know, I'll answer. If I don't, I'll reach out to the Honda folks  and see if I can get an answer. The 450L isn't cheap, so if I can help you make the right decision, my mission will have been accomplished.  Also, you can find a several galleries with lots of photos of the 2019 CRF450L in action, as well as close-ups and tech/service info HERE.
     
    Bryan Bosch, ThumperTalk.com

    #crf450L #ridered #dualsport #blessed #grateful
    Billy@JEPistons
    Whether you're racing or looking for increased performance out on the trail, there are a plethora of performance upgrades to consider to increase the power of your machine. Piston manufacturers like JE Pistons offer high compression piston options for many applications, but there are important merits and drawbacks you should consider when deciding if a high compression piston is right for your application. To better understand, we’ll take a look at what increasing compression ratio does, what effects this has on the engine, detail how high compression pistons are made, and provide a high-level overview of which applications may benefit from utilizing a high compression piston.

    Bumping up the compression in your motor should be an informed decision. It's important to first understand what effects high-compression has, the anatomy of a high-comp piston, and what applications typically benefit most.
    Let’s start with a quick review of what the compression ratio is, then we’ll get into how it affects performance. The compression ratio compares the volume above the piston at bottom dead center (BDC) to the volume above the piston at top dead center (TDC). Shown below is the mathematical equation that defines compression ratio:

    The swept volume is the volume that the piston displaces as it moves through its stroke. The clearance volume is the volume of the combustion chamber when the piston is at top dead center (TDC). There are multiple different dimensions to take into account when calculating clearance volume, but for the sake of keeping this introductory, this is the formula as an overview. When alterations to the compression ratio are made, the clearance volume is reduced, resulting in a higher ratio. Reductions in clearance volume are typically achieved by modifying the geometry of the piston crown so that it occupies more combustion chamber space.
     
    Swept volume is the volume displaced as the piston moves through the stroke, and clearance volume is the volume of the combustion chamber with the piston at top dead center.
    How does an increased compression ratio affect engine performance? To understand how increasing the compression ratio affects performance, we have to start with understanding what happens to the fuel/air mixture on the compression stroke. During the compression stroke, the fuel/air mixture is compressed, and due to thermodynamic laws, the compressed mixture increases in temperature and pressure. Comparatively, increasing the compression ratio over that of a stock ratio, the fuel/air mixture is compressed more, resulting in increased temperature and pressure before the combustion event.
    The resulting power that can be extracted from the combustion event is heavily dependent on the temperature and pressure of the fuel/air mixture prior to combustion. The temperature and pressure of the mixture before combustion influences the peak cylinder pressure during combustion, as well as the peak in-cylinder temperature. For thermodynamic reasons, increases in peak cylinder pressure and temperature during combustion will result in increased mechanical efficiency, the extraction of more work, and increased power during the power stroke. In summary, the more the fuel/air mixture can be compressed before combustion, the more energy can be extracted from it.

    Higher compression allows for a larger amount of fuel/air mixture to be successfully combusted, ultimately resulting in more power produced during the power stroke.
    However, there are limits to how much the mixture can be compressed prior to combustion. If the temperature of the mixture increases too much before the firing of the spark plug, the mixture can auto ignite, which is often referred to as pre-ignition. Another detrimental combustion condition that can also occur is called detonation. Detonation occurs when end gases spontaneously ignite after the spark plug fires. Both conditions put severe mechanical stress on the engine because cylinder pressures far exceed what the engine was designed for, which can damage top end components and negatively affect performance.
     
    Detonation and pre-ignition can spike cylinder pressure and temperature, causing damage. Common signs of these conditions include pitting on the piston crown.
    Now that there is an understanding of what changes occur during the combustion event to deliver increased power, we can look at what other effects these changes have on the engine. Since cylinder pressure is increased, more stress is put on the engine. The amount of additional stress that is introduced is largely dependent on the overall engine setup. Since combustion temperatures increase with increased compression ratio, the engine must also dissipate more heat. If not adequately managed, increased temperatures can reduce the lifespan of top-end components.
     
    JE's EN plating is a surface treatment that can protect the piston crown and ring grooves from potential damage caused by high cylinder pressure and temperature. EN can be an asset for longevity in a high-compression race build.
    Often, additional modifications can be made to help mitigate the side effects of increasing the compression ratio. To help reduce the risk of pre-ignition and detonation, using a fuel with a higher octane rating can be advantageous. Altering the combustion event by increasing the amount of fuel (richening the mixture) and changing the ignition timing can also help. Cooling system improvement can be an effective way to combat the additional heat generated by the combustion event. Selecting larger or more efficient radiators, oil coolers, and water pumps are all options that can be explored. Equipping the engine with a high-performance clutch can help reduce clutch slip and wear which can occur due to the increased power.

    High-level race team machines are great examples of additional modifications made to compensate for increased stress race engines encounter. Mods include things like larger radiators, race fuel, custom mapping, and performance clutch components.
    Let’s take a quick look at what considerations are made when designing a high compression piston. Typically, high compression pistons are made by adding dome volume to the piston crown, which reduces the clearance volume at TDC. In some cases, this is difficult to do depending on the combustion chamber shape, size of the valves, or the amount of valve lift. When designing the dome, it is essential to opt for smooth dome designs. Smooth domes as opposed to more aggressively ridged designs are preferred because the latter can result in hot spots on the piston crown, which can lead to pre-ignition. Another common design option is to increase the compression distance, which is the distance from the center of the wrist pin bore to the crown of the piston. In this approach, the squish clearance, which is the clearance between the piston and head, is reduced.
     
     
    Higher compression is commonly achieved by increasing dome volume while retaining smooth characteristics, as pictured here with raised features and deep valve pockets. Compression height can also be increased, which increases the distance between the center of the pin bore and the crown of the piston.
    A high-level overview of which applications can benefit from increased compression ratio can be helpful when assessing whether a high-compression upgrade is a good choice for your machine. Since increasing the compression ratio increases power and heat output, applications that benefit from the additional power and can cope with additional heat realize the most significant performance gains. Contrarily, applications where the bike is ridden at low speed, in tight conditions, or with lots of clutch use can be negatively impacted by incorporating a high compression piston. Keep in mind these statements are generalizations, and every engine responds differently to increased compression ratios. Below are lists of applications that may benefit from increasing the compression ratio as well as applications where increased compression may negatively influence performance. 
    Applications that may benefit from utilizing a high compression piston:
     Motocross  Supermoto  Drag racing  Road racing  Ice racing  Flat track  Desert racing
    Motocross and less technical off-road racing are two of multiple forms of racing in which high-compression pistons can benefit performance due to higher speeds and better air flow to keep the engine cool. Peick photo by Brown Dog Wilson.
    Applications that may be negatively affected by utilizing a high compression piston:
     Technical off-road/woods riding  Trials  Other low speed/cooling applications
    Lower speed racing and riding may not benefit as much from a high-compression piston, as heat in the engine will build up quicker due to lessened cooling ability.
    Fortunately, if you’re considering increasing your engine’s compression ratio by utilizing a high compression piston, many aftermarket designs have been tested and optimized for specific engines and fuel octane ratings. For example, JE Pistons offers pistons at incrementally increased compression ratios so that you can incorporate a setup that works best for you.
    For example, high-compression pistons from JE for off-road bikes and ATVs are commonly available in 0.5 compression ratio increases. Assume an engines stock compression ratio is 13.0:1, there will most likely be options of 13.5:1 and 14.0:1, so that you can make an informed decision on how much compression will benefit you based on your machine and type of riding.

    From left to right are 13.0:1, 13.5:1, and 14.0:1 compression ratio pistons, all for a YZ250F. Notice the differences in piston dome volume and design.
    If performance is sufficient at an engine’s stock compression ratio, there are still improvements in efficiency and durability that can be made with a forged piston. Forged pistons have a better aligned alloy grain flow than cast pistons, creating a stronger part more resistant to the stresses of engine operation. In addition to forged material, improvements can be made on piston skirt style design to increase strength over stock designs, such as with JE’s FSR designs. JE also commonly addresses dome design on stock compression pistons, employing smoothness across valve reliefs edges and other crown features to improve flame travel, decrease hot spots, and ultimately increase the engine’s efficiency.
     
    Even if stock compression is better for your application; forged construction, stronger skirt designs, and more efficient crown designs can still provide improved performance and durability.
    If it’s time for a new piston but you’re still not sure what compression ratio to go with, give the folks at JE a call for professional advice on your specific application.
    Kevin from Wiseco
    Wiseco's new Garage Buddy engine rebuild kits offer everything you need for a bottom and top end rebuild. From the crank to the piston kit, and even an hour meter to track maintenance, everything is included in one box. Here we take a look at the components included, and the technology behind them.

    So, the time has come for an engine rebuild. Hopefully it’s being done as a practice of proper maintenance, but for many it will be because of an engine failure. Whether the bottom end, top end, or both went out, the first step is to disassemble and inspect. After determining any damage done to engine cases or the cylinder, and arranging for those to be repaired/replaced, you’re faced with choosing what internal engine components to buy, where to get them, and how much the costs are going to add up.
    A full engine rebuild is a serious job and requires a lot of parts to be replaced, especially in four-strokes. You have to think of bottom end bearings and seals, a crankshaft assembly, piston, rings, clips, wristpin, and the plethora of gaskets required for reassembly. If you’re doing this rebuild yourself, or having your local shop do the labor, chances are you don’t have a factory team budget to spend on parts. However, you know you want high-quality and durable parts, because you don’t want to find yourself doing this again anytime soon.

    Rebuilding a dirt bike engine is an involved job, requiring many parts to be replaced. Missing one seal or gasket can put the whole rebuild on hold.
    You could source all the different parts you need from different vendors to find the best combination of quality and affordability. But, it can get frustrating when 6 different packages are coming from 6 different vendors at different times, and each one relies on the next for you to complete your rebuild.
    Wiseco is one of the manufacturers that has been offering top end kits (including piston, rings, clips, gaskets, and seals) all in one box, under one part number for many years. Complete bottom end rebuild kits are also available from Wiseco, with all necessary parts under one part number. So, it seemed like a no brainer to combine the top and bottom end kits, and throw in a couple extra goodies to make your complete engine rebuild in your garage as hassle free as possible.
     
    Top-end piston kits and bottom-end kits come together to create Wiseco Garage Buddy rebuild kits.
    Wiseco Garage Buddy kits are exactly as the name implies, the buddy you want to have in your garage that has everything ready to go for your engine rebuild. Garage Buddy engine rebuild kits come with all parts needed to rebuild the bottom and top end, plus an hour meter—with a Garage Buddy specific decal—to track critical maintenance intervals and identify your rebuild as a Garage Buddy rebuild. The kits include:
    Crankshaft assembly OEM quality main bearings All engine gaskets, seals, and O-rings Wiseco standard series forged piston kit (piston, ring(s), pin, clips) Small end bearing (for two-strokes) Cam chain (for four-strokes) Hour meter with mounting bracket and hour meter decal   
    Open up a Garage Buddy kit, and you'll find all the components you need to rebuild your bottom and top end.
    2-stroke and 4-stroke
    Whether your machine of choice is a 2-stroke or a 4-stroke, Wiseco can help you with your rebuild. 2-stroke Wiseco Garage Buddy kits include everything listed above, featuring a Wiseco forged Pro-Lite piston kit. You don’t even have to worry about sourcing a small-end bearing, that’s included too. 2-stroke fans often brag about the ability to rebuild their bikes so much cheaper than their 4-stroke counterparts, and they’ll have even more ammo for bragging now with these kits starting in the $400 range.

    A Wiseco 2-stroke Garage Buddy kit includes all the parts you'll need for piston and crankshaft replacement, plus an hour meter to track your next maintenance intervals.
    However, don’t abandon your 4-stroke yet. Many riders cringe—and rightfully so—at the thought of rebuilding their 4-stroke because of the costs associated, but Wiseco 4-stroke Garage Buddy kits starting in the $600s takes a lot of sting off your rebuild project. They even include a new timing chain.
    No matter what you’re rebuilding, you’ll be able to track key maintenance intervals for your fresh engine with the Wiseco hour meter and log book that’s included in the Garage Buddy kits. All Garage Buddy kits include a specific hour meter decal as well, which is important for the limited warranty to identify the rebuild as a Garage Buddy rebuild.

    A Wiseco 4-stroke Garage Buddy kit includes all the parts you'll need for piston and crankshaft replacement, including a cam chain and an hour meter.
    Ease of ordering
    Wiseco Garage Buddy kits come with the listed parts boxed up in one box, and listed under one part number, which makes it nice to not have to worry about if you might’ve missed something when ordering. Simply find the single part number for your model, order, and you’re on your way to brand new performance.

    Quality Performance, backed by a Limited Warranty
    Ordering convenience doesn’t make a difference if the parts do not provide quality and reliability. Wiseco crankshafts are designed completely by in-house engineers, who determine all assembled dimensions, clearances, materials, and specifications. These specifications have been determined from R&D tests such as hand inspection, dyno, and failure analysis.
    Once Wiseco cranks have been manufactured to exact specifications they are batch inspected, and critical tolerances and dimensions are measured. Major inspections and tests include crank run-out and trueness, because they must operate within a strict tolerance to last long and perform well.

    Wiseco crankshafts and bearings are manufactured and tested according to strict tolerances and clearances, including run-out and trueness. Crankshaft designs are also tested for 4 hours at WOT.
    Bearings are another critical point of inspection. Wiseco has worked to build relationships with top-tier bearing suppliers to provide a long lasting, low-friction product. Debris in a bearing can lead to very fast wear, and Wiseco makes it a point to inspect batches of bearings for cleanliness and proper operation.
    As part of the design and engineering process, prototype crankshafts are hand inspected and dyno-tested at wide open throttle for 4 consecutive hours. This is a benchmark test, and new crankshaft designs must pass it before to be deemed worthy for manufacturing.

    Watch our crank R&D and inspection process.
    A Warranty on Engine Internals?
    Yes! Wiseco is committed to providing performance and reliability in all their products. This is why Garage Buddy kits come with a limited warranty. Rebuild your engine with a Garage Buddy kit, and your new Wiseco components are covered against manufacturer defects for 90 days from the date of purchase, or 10 hours logged on the hour meter, whichever comes first. Check out all the warranty details on the detail sheet in your new Garage Buddy kit.

    Open up your Garage Buddy kit and you'll find a detail sheet on the warranty on your new components.
    Forged Pistons
    The top end kits included in Garage Buddy kits feature a Wiseco forged piston, which are designed, forged, and machined completely in-house in the U.S.A. Four-stroke Garage Buddy kits come with a Wiseco standard forged piston, which offers stock compression and more reliability and longevity, thanks to the benefits of the forging process.
    Two-stroke Garage Buddy kits include a Wiseco Pro-Lite forged piston, which is the two-stroke piston that has been providing two-stroke riders quality and reliability for decades. Some applications, two and four-stroke, even feature ArmorGlide skirt coating, reducing friction and wear for the life of the piston.
    Forged aluminum has an undeniable advantage in strength over cast pistons, thanks to the high tensile strength qualities of aluminum with aligned grain flow.
    Read more about our forging process here, and get all the details on our coatings here.
     
    All Wiseco pistons are forged in-house from aluminum. Some pistons may also come with ArmorGlide skirt coating, and some 2-stroke pistons may already have exhaust bridge lubrication holes pre-drilled.
    All pistons are machined on state-of-the-art CNC machine equipment, then hand finished and inspected for quality. The forged pistons come complete with wrist pin, clips, and high-performance ring(s).
    Lastly, all gaskets and seals are made by OEM quality manufactures. Sealing components are not something to ever go cheap on, because no matter how high-quality your moving components are, if your engine is not sealing properly, it’s coming back apart.
    Need some tips on breaking in your fresh engine? Check this out.
     
    Gaskets and seals provided in Wiseco Garage Buddy kits are OEM quality, ensuring your freshly rebuilt engine is properly sealed.
    Kevin from Wiseco
    Find out how to relieve an exhaust bridge and drill lubrication holes in 2 stroke applications, so you can get the most out of your piston!
    When you order a new Wiseco 2-stroke piston and open up the box and read the instructions, you might see something like “follow these steps to drill the lubrication holes.” There’s no doubt that the thought of drilling holes in your new piston can be scary and intimidating. But not to worry! We’ll get you through it right here with all the information you need and a step-by-step. Relieving the exhaust bridge and drilling lubrication holes is a common part of the 2-stroke top end replacement process, but the importance of performing these steps is unrealized by many and neglected too often.

    Drilling lubrication holes is a simple but important process for many 2 stroke applications.
    So, what is an exhaust bridge?
    First things first, not all 2-stroke cylinders have an exhaust bridge. So if your cylinder does not have one, drilling holes in your piston is not necessary.
    The exhaust bridge is the thin strip of metal that separates the exhaust ports in the cylinder. Whether you look into the exhaust ports through the exhaust outlet or through the cylinder bore, if you see a thin metal wall separating your exhaust ports, that is your exhaust bridge. For the purpose of installing a new Wiseco piston, the area of concern is the edge of the exhaust bridge on the inside of the cylinder bore.

    The exhaust bridge is the edge of the wall separating the exhaust ports on some 2 stroke cylinders.
    Why do I need to relieve the exhaust bridge?
    Now that we know what the exhaust bridge is, it’s important to understand why we feel this machine work is essential to replacing a 2-stroke top end. The most heat in your motor is generated from combustion in the cylinder during normal operation. Specifically, the exhaust port(s) of the cylinder are exposed to the most heat because this is the only way out for the hot gas produced during combustion. This means that under normal running conditions, your piston and your exhaust bridge are constantly under the pressure of extreme heat.
    Wiseco pistons are made from forged aluminum, which offers more strength and reliability, but also expands faster under heat than an OEM cast piston. The exhaust bridge will also expand more than the rest of the cylinder because it is such a thin structure. The lack of material makes it harder for heat to dissipate before it affects the aluminum and causes expansion. 
    Expansion under heat is normal, but must be compensated for to make sure you get the most life and best performance out of your top end. Relieving the exhaust bridge simply means taking a small amount of material off the face the bridge in order to make room for expansion. If there wasn't any extra clearance, the exhaust bridge would expand past the cylinder wall once your motor heats up. This leads to scoring on the piston as it comes into contact with the exhaust bridge, especially as the piston expands at the same time.

    Notice the small amount of material taken off of the exhaust bridge, and the blending back into the cylinder. Read below on how to accomplish this.
    Relieving the Exhaust Bridge
    Now that we have some understanding established, let’s go through how to get it done. As always, if you don’t feel comfortable doing this work, this can commonly be done by the shop performing your cylinder work. If you have the rights tools, this can be done in the garage on cast iron and steel cylinder bore liners. We recommend using a die grinder with a small sanding roll to gently remove .003” of material off the cylinder wall face of the exhaust bridge.
    After the material is removed, the machining must be blended with the rest of the cylinder wall at the top and bottom of the exhaust bridge. You want to make sure there’s an easy slope for the piston ring to slide over when entering and exiting the exhaust bridge relief. If your cylinder is lined with Nikasil, this process will not work because that material is too hard. Your exhaust bridge must be relieved before being lined with Nikasil to achieve the same result. Check with the shop you choose for your cylinder work if you are unsure.
    Why do I need to drill holes in my piston?
    Relieving the exhaust bridge will make sure there’s no expansion past the cylinder wall, but we still want to make sure we keep the heat as low as possible. With small holes drilled into the skirt of the piston, oil underneath the piston will makes its way through the holes, and lubricate the contact point between the piston and exhaust bridge. Better lubrication means less friction, and less friction means less heat, which is what we want to make sure we don’t have any abnormal wear.
    Drilling Lubrication Holes
    Make sure you have the instruction sheet that came with your new piston. This drilling information can also be found there, complete with a visual diagram.

    Be prepared with your instruction sheet.
    1. Install the piston and wrist pin on the connecting rod with one circlip. Make sure the arrow stamped on the dome of the piston is facing the exhaust side of the cylinder.
    2. Slide the cylinder over the piston until the cylinder is in its normal position on the crankcase.

    Temporarily install the piston on the connecting rod and slide the cylinder over the piston.
    3. Slowly turn the engine over until the bottom ring groove (or the only ring groove if your piston has only one) on the piston is at the top of the exhaust bridge. You can look through the exhaust port of the cylinder to help know when the piston is in the correct spot.
    4. Go through the exhaust port with a pencil and trace a line on the piston skirt for each side of the exhaust bridge.

    Trace two lines on the piston, one on each side of the exhaust bridge.
    5. Once the lines are traced and visible, remove the cylinder and the piston.
    6. Start .300” below the bottom ring groove and mark two points .375” apart from each other. Make sure the points are centered horizontally between the two lines you traced.
     
    Use the proper measurements to mark 2 points for the holes to be drilled.
    7. Drill two holes .060” - .090” in diameter (1/16” or 5/64” drill bit) on your marked points (one hole on each point).

    Drill holes on your marked points with one of the specified drill bits.
    8. Remove all burrs from drilling the lubrication holes. On the inside of the piston, lightly sand with 400-600 grit sand paper. On the outside of the piston, use a ¼” drill bit and twirl it between your fingers over the holes you drilled to break away any edges and imperfections.
    9. Wash the cylinder and piston with soap and water, and use compressed air to remove any water and debris.
    10. Wipe the cylinder wall with light coat of oil. Whichever 2-cycle oil you normally use is fine.
    11. Continue your top end rebuild as normal.
     
    This is how your final product should look all cleaned up and deburred.
    Why doesn't Wiseco pre-drill the holes in the pistons during manufacturing?
    Some Wiseco two-stroke pistons do come with these lubrication holes pre-drilled. However, there are certain applications that use the same piston across a wide range of model years, but the location of the exhaust ports across those years changes. Therefore, while the piston remains the same, the location of the lubrication holes will vary based the specific year cylinder for certain applications.
    Want to see the latest in 2-stroke piston technology? Read about the Wiseco 2-Stroke Racer Elite pistons here.
    See all that Wiseco has to offer for your 2-stroke here.
    Bryan Bosch
    All-new RM-Z250 and DR-Z50 top the list of updated and returning models 

    BREA, CA – July 17, 2018 – (Motor Sports Newswire) –  Led by the advance look at an all-new RM-Z250 motocross machine and the new DR-Z50 mini, Suzuki Motor of America (SMAI) is proud to announce the introduction of its 2019 Motocross, DualSport, Off-road and Youth models including the QuadSport Z90 and QuadSport Z50 ATVs. The completely updated RM-Z250 features a long list of enhancements and performance improvements and now mirrors the cutting-edge styling of its big brother RM-Z450, introduced just last year. For young riders just starting out, Suzuki offers the new DR-Z50 mini. Featuring a host of convenience and safety features, the DR-Z50 is the perfect way to introduce youngsters to the thrill of dirt bike riding.
    All-new from the ground up in 2018, the RM-Z450 returns with key updates to its suspension while Suzuki’s versatile DualSport and DR-Z400SM models continue to provide owners with class-leading performance whether riding on- or off-road. For those ready to take Suzuki’s renowned motocross bike handling to the trails, the RMX450Z returns for serious desert and woods riders. The DR-Z125L is everyone’s favorite trail bike and returns with RM-Z inspired graphics.
    2019 Motocross Models
    Suzuki’s tradition of building championship winning, high performance motocross machines takes the next step forward with the pre-announcement of the all-new, 2019 RM-Z250. Designed to move it to the head of the 250 class, this all-new stunner features a long list of enhancements and performance improvements. Preliminary information on this new motorcycle is available now with full product details and specifications set to be announced in September.
    Evolving the fundamental performance elements of ‘RUN’, ‘TURN’ and ‘STOP’ to a new level, Suzuki has infused the Winning Balance into the new 2019 RM-Z250.
    Suzuki engineers have achieved an even greater level of balance between the race-proven performance of the RM-Z250’s engine and chassis. Particular attention was focused on advancing its ‘TURN’ capabilities to continue Suzuki’s tradition of producing the best handling motorcycles on the racetrack.
    The styling of the RM-Z250 is all-new and unified with that of the RM-Z450.

    NEW 2019 RM-Z250
    New Aluminum Frame & Swingarm More Power and Improved Throttle Response Sleek New Bodywork & Ergonomics New Coil-spring Fork & Shock/Linkage Champion Yellow with Red/Blue Graphics MSRP $TBA Estimated arrival at dealers: February 2019 *Additional information will be available in September 2018
    With a decade’s worth of race win dominance, the 2019 RM-Z450 remains the champion’s choice. Fully-revised in 2018, the RM-Z450 returns with its sleek, race-ready appearance, strong engine and a nimble chassis that continues Suzuki’s tradition of having the best handling 450. To further improve the agile RM-Z450, a new spring has been fitted to the SHOWA BFRC shock with new damping force settings while the coil-spring fork has new damping-force settings as well. Continual improvement is why the RM-Z450 remains the class standard for cornering performance.

    2019 RM-Z450
    DOHC 4-valve, 449cc, 4-stroke Engine Suzuki EFI with Tuning Coupler System Twin-spar Aluminum Frame & Swingarm New Rear Shock Spring Updated Suspension Settings Champion Yellow with Red/Blue Graphics MSRP $8949 Estimated arrival at dealers: August 2018
    2019 RM85
    The Choice of Future Champions Strong & Reliable 84.7cc Two-stroke Engine Six-speed Transmission & Manual Clutch Fully Adjustable SHOWA Suspension Champion Yellow with Red/Blue Graphics MSRP $4199 Estimated arrival at dealers: November 2018
    Enlist in the RM ARMY and enjoy Suzuki Amateur Racing Support!
    Suzuki’s renowned RM Army and Amateur Racing Support continues, offering over $3.8 million in contingency, trackside support, and the opportunity to train with Ricky Carmichael at Suzuki’s exclusive Camp Carmichael. Want to see why champions choose Suzuki? Visit www.racesuzuki.com for more information on Suzuki’s Amateur Support Program and enlist in the RM ARMY!
    2019 DualSport Models
    Suzuki offers the best all-around selection of DualSport models in the industry. As evident with the DR-Z400S, Suzuki DualSport models are fun, reliable and capable motorcycles available to anyone who’s ready to take a ride down an off-road trail or ribbon of asphalt. The versatile DR650S sports the ability to reduce its chassis and seat height for rider comfort and confidence while the DR200S is at home trail riding or commuting; delivering an impressive 88 MPG.

    2019 DR650S
    644cc, Air and Oil-cooled, Four-stroke Engine Push-button Electric Start & Street-legal Lighting Optional Adjustable Seat Height Smooth-shifting 5-speed Transmission Solid Black with Red Graphics MSRP $6599 Estimated arrival at dealers: August 2018
    2019 DR-Z400S
    Liquid-cooled, 398cc DOHC Engine Push-button Electric Start & Street-legal Lighting Slim Chassis with Fully-adjustable Suspension Spoke-style wheels, Aluminum 21” and 18” Rims Solid White Bodywork with Blue/Black Graphics MSRP $6749 Estimated arrival at dealers: November 2018
    2019 DR200S
    199cc OHC, Four-stroke Engine Low 33.3” Seat Height & 278 Ready-to-Ride Pounds Push-button Electric Start & Street-legal Lighting Over 8-inches of Front and Rear Suspension Travel, Solid White Bodywork with Blue/Black Graphics MSRP $4649 Estimated arrival at dealers: August 2018
    2019 Suzuki DR-Z400SM
    Suzuki’s DR-Z400SM combines a narrow, off-road capable chassis with street-legal components to produce a lightweight, Supermotard package that turns, accelerates, and stops better than many sportbikes. The DR-Z400SM has an inverted front fork, wide, spoke-style wheels sporting sportbike tires, and a 300mm floating front brake rotor. There are two color choices for the 2019 DR-Z400SM; Solid White bodywork with red/black graphics plus gold-anodized EXCEL rims on the wheels, or white bodywork with blue/black graphics and blue-anodized rims.
    2019 DR-Z400SM
    Liquid-cooled, 398cc DOHC Engine Push-button Electric Start & Street-legal Lighting Inverted, Fully-adjustable RM-style Fork Solid White Bodywork with Red/Black Graphics with Wide, Spoke-style Wheels with Gold-anodized Rims 120/70-17 & 140/70-17 Sportbike Tires -Or-
    Solid White Bodywork with Blue/Black Graphics with Wide, Spoke-style Wheels with Blue-anodized Rims MSRP $7349 Estimated arrival at dealers: September 2018  
    2019 Off-road Models
    The new 2019 DR-Z50 is a high-quality, Suzuki-built mini-bike that brings ease and convenience to riders just getting started on two wheels. With an automatic clutch, 3-speed transmission, electric starting and a low 22-inch seat height, this RM-styled bike will help build confidence and riding ability for young, supervised riders. The 49cc engine delivers a smooth, controllable power-band plus adult supervisors can adjust the power level so young riders can learn at a proper pace.
    Joining the DR-Z50 is the DR-Z125L that’s ideal for riders of intermediate stature and skill, and the RMX450Z that combines elements of the championship-caliber RM-Z450 with features needed for serious trail work.

    2019 DR-Z50 NEW
    Reliable 49cc, 4-stroke Engine Smooth-shifting 3-speed Transmission & Auto-clutch Push-button electric starting with back-up kick starter Keyed Ignition & Power Limiter for Parental Control Inverted Fork & Single Rear-shock Champion Yellow with Red/Blue Graphics MSRP $1749 Estimated arrival at dealers: September 2018
    2019 DR-Z125L
    Compact & Reliable 124cc 4-stroke Single Smooth-shifting Transmission, Easy-pull Manual Clutch Strong Steel Frame & Beam-style Swingarm Telescopic forks & Single, Link-type Rear Suspension Champion Yellow Bodywork with RM-Z Style Graphics MSRP $3299 Estimated arrival at dealers: August 2018
     
    2019 RMX450Z
    Enduro-ready Off-road Bike based on the RM-Z450 Electric-starting with Kick-start Back-up Competition-ready Instruments and Lighting Black-anodized Wheels with 18-inch Rear Rim Fully-adjustable, SHOWA Fork & Rear Shock Champion Yellow with Red/Blue Graphics MSRP $8999 Estimated arrival at dealers: August 2018  
    Each new Suzuki DualSport, SuperMoto, Off-road, and ATV model is backed by our Limited Warranty1. Additionally the coverage period and other benefits added through Suzuki Extended Protection. Click here to learn more or visit a Suzuki dealer for details.
    1The DR200S, DR650S, DR-Z400S, DR-Z400SM models are covered by Suzuki’s On-road, 12-month Limited Warranty. The DR-Z50, DR-Z125L and RMX450Z models are covered by Suzuki’s Off-road, 6-month Limited Warranty. The QuadSport Z50 and QuadSport Z90 models are covered by Suzuki’s ATV, 12-month Limited Warranty. The competition RM85, RM-Z250 and RM-Z450 models do not have warranty coverage.
    About Suzuki
    Suzuki Motor of America, Inc. (SMAI) distributes Motorcycles, ATVs, Scooters, Outboard Motors and Automotive Parts and Accessories via an extensive dealer network throughout 49 states. Suzuki Motor Corporation (SMC), based in Hamamatsu, Japan, is a diversified worldwide manufacturer of Motorcycles, ATVs, Scooters, Automobiles, Outboard Motors and related products. Founded in 1909 and incorporated in 1920, SMC has business relations with 201 countries/regions. For more information, visit www.suzuki.com
    Suzuki, the “S” logo, and the Suzuki model and product names are Suzuki trademarks or ®.
    Source: Suzuki Motor of America, Inc.

    ronbuell
    Ever been bored or really ticked off by not being able to reach your fuel screw for trailside adjustments?  Well, I decided to do something about it, and not spend a bunch of money to boot!
    Parts liste included:
    Short length of brass tube. Short piece of old, broken speedometer inner cable. Nut from the rejects bin.   I welded the nut to the speedometer cable inner and soldered the other end to the fuel screw using the brass tube as a connector.  I didn't need or fab up a holder for the end, but I wouldn't be too hard. My DIY flexible fuel mixture screw works great and the price is right! I highly recommend this mod.

    Cheap, but effective DIY fuel mixture screw
    Rob@ProX
    Rebuilding a top end is a task most two-stroke owners will run into at one point or another. Here, we go over critical steps and key tips to installing a new piston and ring(s) in your two-stroke.
    Periodically, if you own a two-stroke, there will come a point where you need to rebuild the top end of your engine. Hopefully, this won’t come as a surprise to you and will be part of your planned maintenance schedule versus experiencing an unplanned engine failure. While two-stroke engines are relatively simple mechanical devices, rebuilding them requires knowledge of how they work, attention to detail, and a systematic approach.

    We’re going to cover numerous tips pertinent to two-stroke top end rebuilds. These tips will be discussed chronologically and will encompass all phases of the build from pre-rebuild prep, to disassembly, through post build. The tips we’re going to share shouldn’t be considered inclusive of everything that has to be done, but are tips that focus on things that are either often overlooked or incredibly important. Let’s get started!
    Pre-Teardown
    Diagnosis  - Before tearing the engine apart, are there any signs that a specific problem exists? If so, are there any diagnostic tests such as compression or crankcase leak down that are worth performing?

    Before tearing your engine down, asses the specific problem with you're engine if you're rebuilding due to a running problem.
    Clean Machine - Take time to thoroughly clean the machine before opening up the engine, especially if you will be servicing the top end without removing the engine from the machine.
    Service Manual - Performing engine maintenance without an OEM factory service manual is not recommended. Make sure you have a manual for your machine prior to starting work. The manual is the only place you’ll find service limits, torque specs, and other key data.
    Disassembly
    Limit Contaminants - Once the cylinder has been removed wrap a clean, lint-free rag around the top of the crankcase. Dirt is one of the leading causes of engine wear, and limiting the opportunity for dirt to enter the crankcase is very important.

    Keep a lint-free rag at the top of the crankcase at all times while it is open and exposed to potential contaminants.
    Piston Removal - Easy piston circlip removal can be accomplished by using a pick and needle nose pliers. Insert the pick into the dimple in the piston and behind the circlip. Then use it as a lever and pry the circlip out partially. Once out partially, grab the circlip with needle nose pliers. During this process, be careful not to scratch or mar the wrist pin bore as this will make removing the wrist pin much more difficult.

    Use tools as needed to aid in circlip removal, but be careful not to mar the pin bore so the wrist pin can be easily removed.
    The ease of pin removal will be largely dependent on the engine design and condition of the bore. If the pin can be removed by hand, great, if not, light tapping while supporting the rod is permissible. Otherwise, a pin puller should be utilized which can be bought or made. In its simplest form, this can consist of an appropriately sized bolt, nut, and socket. Once the wrist pin has been removed, the piston can be removed from the rod.

    Hopefully, the wrist pin can be removed by hand once the circlip is out. If not, an appropriately sized socket with some light tapping from the opposite end can help break it loose.
    Power Valve Disassembly - Prior to taking the power valve system apart, spend some time reviewing the procedure in your service manual. For additional insight into how the components interact, review the exploded views in the service manual and look at part microfiches, which can be found online.

    Online microfiches can be very helpful to double-check reassembly of the power valve. They can be found on many motorcycle dealer websites.
    When removing the power valve system, consider laying the components out on a clean rag in an orientation that correlates to how they are installed in the engine. This is a relatively simple thing to do that will help you remember how they are installed later. When it comes to cleaning the components, clean them one at a time or in small batches so that they don’t get mixed up.

    Lay out all the parts of your power valve assembly as you disassemble it. This will help you keep everything organized, and make sure you get it back together correctly.
    Inspection
    Reed Valve - Don’t forget to check the condition of the reed valve petals, cage, and any stopper plates. Most service manuals will detail the acceptable clearance between the petal tips and cage as well as the stopper plate height. Ensure any rubber coatings on the reed cage are in good condition.

    Inspect all reed valves components thoroughly before reassembling the top end. Any parts showing signs of excessive wear or damage should be replaced.
    Intake Manifold - Check the intake manifold for cracks. Cracks are more common on older engines, and propagation all the way through the manifold can lead to air leaks.
    Exhaust Flange - Check the condition of the exhaust flange and ensure that it is not excessively worn. An excessively worn flange will make exhaust gas sealing difficult, hamper performance, and leak the infamous spooge. 
    Power Valve Components - Take a moment to review the condition of all the power valve components. Significant wear can occur over time and lead to performance losses.
    Rod Small End - Check the small end rod bore for surface defects such as pitting, scratches, and marring. Any severe defects in the bore will necessitate rod replacement.

    The rod small end is a critical point of inspection. Any damage to the inside surface could affect the small end bearing, leading to a chain of top end problems and potential failure.
    Sourcing New Components
    When freshening up the top end in your two-stroke, it’s important to reassemble with quality components. A deglazed and honed or bored and replated cylinder is a critical component to ensuring reliable performance from your new top end. Your local cylinder shop should be able to handle the bore and replate when necessary, and a simple deglazing can be accomplished with a Scotch-Brite pad. Be sure to retain the 45-degree honing mark angle.
    There are a lot of choices for new pistons from the aftermarket out there, but many people choose to stick to OEM. However, when ordering from the OEM, every individual part must be ordered separately, including the piston, ring, pin, clips, gaskets, etc. Dealing with all these part numbers and chancing forgetting a component can be a pain, and get expensive.

    ProX two-stroke pistons are manufactured by OEM suppliers, and come with the piston, pin, ring(s), and circlips all under one part number.
    ProX two-stroke pistons are manufactured by the same OEM-suppliers to exact OE specs. They are available in A, B, C, and D sizing for most applications. ProX pistons come with the piston, ring(s), pin, and clips all in one box. Complete top-end gasket kits can even be ordered under one part number. ProX pistons provide an OEM-replacement option with less hassle and less strain on your wallet.
    Find ProX pistons for your bike here.

    Even though ProX pistons are made by OE suppliers, the quality control difference is evident. On the left is a ProX piston for a Honda CR250, and on the right is a brand new piston out of the box from Honda. Which would you choose?
    Measurements
    The number of measurements that should be taken throughout the top end rebuild will be discretionary. At ProX, we strive for excellence and err on the side of caution when it comes to engine building, so our builds consist of numerous measurements and inspections prior to reassembly. For us, this ensures a high level of confidence and safeguards against external oversights. We recommend the same to anyone building an engine.
    Below is a list of measurements that we routinely make when rebuilding a two-stroke top end:
     Piston ring end gaps  Piston-to-cylinder clearance  Rod small end diameter Out of these measurements, confirming or adjusting the ring end gaps is by far the most important, followed closely by ensuring the cylinder bore is within spec with respect to diameter, straightness, and roundness. Understandably, some measurements may be difficult for the average home builder to execute, usually due to not having the right equipment, however, a competent shop should be able to assist.
    Ring end gaps can be checked by installing the ring in the bore without the piston, and using a feeler gauge to find the measurement. Correct ring end gap is listed in the installation instructions that come with a new ProX piston.

    ProX rings often do not need to be filed as they are pre-gapped, but it's always a good idea to make sure your end gap is within the provided spec.
    Piston-to-cylinder is another measurement that should be checked before final assembly. For this, use a bore guage and a set of calipers to measure the bore size. Next, grab a set of micrometers and measure the piston. ProX pistons should be measured perpendicular to the wrist pin, a quarter of the way up the piston skirt from the bottom. Subtract your piston size measurement from your bore size, and you have your piston-to-cylinder clearance. ProX pistons come with a chart on the instruction sheet that shows the range your clearance should be in.
      
    Measuring piston-to-cylinder clearance is a smart precaution to help ensure you won't run into any unexpected issues with your new top end.
    A final measurement we recommend taking is the rod small end diameter. This is important because sometimes these can get worn out and create free play for the small end bearing, resulting in damage to the bearing and most likely the entire top end. It can be done using the same method as the bore diameter. Compare your measurement to the acceptable range in your owner's manual.

    Making sure the diameter of the small end of the rod is within spec is often overlooked, but can prevent a serious top end failure.
    Prep Work
    Cylinder Cleaning - Once the cylinder has been deglazed or has come back from replating, it should be cleaned one final time. There is almost always leftover honing grit that will need to be removed. To effectively clean the cylinder, use warm soapy water and a bristle brush, followed by automatic transmission fluid or a similar cleaning solution and a brush or lint-free rag. To check the cleanliness of the cylinder, rub a cotton swab around the bore and look for contaminants. Clean the bore until no contaminants are visible on the cotton swab. Any honing grit that remains in the cylinder will facilitate premature wear of the piston rings.

    A clean, de-glazed, and properly honed cylinder is key to piston and ring function and longevity.
    Power Valve Function - Cylinders that have been exchanged or replated should have the power valve system reinstalled ahead of final installation. Often times, excess plating can inhibit power valve movement. To correct this, the excess plating must be carefully removed. On cylinders utilizing blade style power valves, the blade position with respect to the cylinder bore should be checked to ensure the blade does not protrude into the bore.

    Assemble the power valve before installing the new piston and reinstalling the cylinder. Be sure to check that the power valve is moving as it should, and not protruding into the bore.
    Piston - It is usually easiest to prepare the new piston as much as possible by installing one of the circlips and the ring pack ahead of joining it to the connecting rod. Unless your service manual dictates which circlip must be installed first, choose the easiest installation orientation. Typically, your dominant hand and preferred work orientation will dictate which side you choose to install the circlip on.
     
    It's easier to install one clip and the piston ring(s) before fixing the new piston to the connecting rod.
    Reference your service manual to determine the correct orientation of the circlip. Usually, the open end of the circlip should be oriented to the 12 or 6 o’clock position. Temporarily install the wrist pin and use it as a backstop so that the circlip is forced to move into its groove. Installing the circlip should be done by hand to limit the chance of deformation. Orient the circlip to the desired position, then push the open ends of the circlip into position first. Be careful not to scratch or mar the wrist pin bore in the process! Once installed, use a pick or screwdriver to confirm the circlip is fully seated and does not rotate. Any circlips that can be rotated must be replaced because they have been compromised and deformed during installation.

    Make sure to note the orientation of each clip after installation. Some manuals may recommend specific positions depending on the piston, but always be sure the gap is not lined up with or near the dimple(s).
    Rings - The compression ring(s) will be directional, and the top of the ring is typically denoted by markings near the end gaps. Apply a thin coat of oil to the ring, then carefully work the ring into position, making sure to line up the ring end gaps with the locating pin in each ring groove.

    Install the ring(s) with the marking(s) facing up, and make sure the ring end gap is lined up with the locating pin in the ring groove.
    Installation
    Piston - On the top of the piston, an arrow will be imprinted, which typically denotes the exhaust side of the piston. Consult your service manual to confirm the proper orientation of the arrow and piston. Apply a light amount of assembly lube to the small end bearing and wrist pin bore on the piston, then install the bearing. Align the piston with the small end of the rod, and slide the wrist pin into place. Once again, use the wrist pin as a backstop, then install the remaining circlip into position. Use a pick or screwdriver to confirm it is fully seated and does not rotate.

     Don't forget to apply some assembly lube to the ring and piston skirts before assembly!
    Cylinder to Piston - In most applications, a ring compressor is not required to compress the rings and install the piston into the cylinder. Lightly oil the cylinder bore with assembly lube or engine oil, then lube the piston skirt and ring faces. Prior to installing the piston and rings, confirm one final time that the piston ring ends are oriented correctly to their respective locating pins.
     
    Once the new piston is installed on the connecting rod, apply some assembly lube to the cylinder wall, and carefully slide the cylinder over the piston. Squeeze the ring with your hand as you slide the cylinder on, simultaneously making sure the ring end gap remains aligned with the locating pin.
    Position the piston at or near TDC then carefully lower the cylinder bore down onto the piston. Use your fingers to compress the ring(s) and ensure the cylinder bore is square to the piston. Feel how easily the cylinder slides over the piston and rings. The installation of the cylinder should be smooth and offer little resistance. If resistance is felt, stop immediately and assess the ring pack. Occasionally one of the rings may come out of position in its groove and snag the cylinder bore. This typically happens as the ring transitions out of your fingers and into the cylinder bore.
     
    Once the cylinder is safely over the ring, slide it all the way on keeping the piston at top dead center (TDC). Don't forget to torque your cylinder and head nuts to the specification listed in your manual.
    Post Build
    Torquing - Your cylinder and head nuts should always be torqued to the specifications outlined in your service manual. Double check all the nuts are set at their corresponding specs.

    Spark Plug - Don’t forget to install a new spark plug and if necessary gap it appropriately.
    Air Filter - Be sure to install a clean air filter prior to start up.
    Crankcase Leak Down Test - As one final precautionary measure perform a crankcase leak down test. A crankcase leak down test will help confirm all the seals, gaskets, and joints are sealing as they should.
    Break-In - When running your new top end for the first time, keep the engine slightly above idle, with slow and mild revs until the engine starts to get too hot to touch. Then, shut the engine off and let it cool until it is warm to the touch. Repeat this process, revving slightly higher and letting the engine get partially hotter each time. After 3 cycles like this, let the engine completely cool, then check all your fluids and re-check the torque on your cylinder and head bolts.
    Once that is squared away, you can begin break-in runs riding the bike. Make sure to keep the RPMs varied while riding for the first time, not letting the engine lug or sit at idle. A safe bet would be to ride the bike like this for 5 minutes, then 10 minutes, and finally 15 minutes, with adequate cooling in between. This will ensure your piston ring(s) are evenly and properly broken in. It’s never a bad idea to double check your fluids and torque one more time after complete cool down.

    Bryan Bosch
    Engineering, development, engine production and vehicle assembly into one location and will increase efficiency. Nearly 700,000 square foot facility on a site covering more than 40 acres. This all new facility will produce the majority of Suzuki two-wheeled products for U.S. distribution.  
    New Facility Merges Three Separate Facilities and Positions Suzuki for Continued Growth
    BREA, CA – June 26, 2018 – (Motor Sports Newswire) –  Suzuki Motor of America, Inc (SMAI), is happy to announce the creation of a new manufacturing plant in Hamamatsu, Japan, home to its parent company, Suzuki Motor Corp. (SMC). The new facility will combine engineering, development, engine production and vehicle assembly into one location and will increase efficiency in the production and delivery of Suzuki’s ever-diversifying motorcycles..
    Originally announced in 2014, this five-year consolidation plan is near completion. Previously, Suzuki motorcycles were developed and manufactured across three locations in Japan – product engineering and development teams worked at the company’s Ryuyo facility; Suzuki produced engines at its Takatsuka plant; and motorcycle assembly lines operated at its Toyokawa plant. These three operations will now be centralized into the new Hamamatsu Plant in the Miyakoda district, in a nearly 700,000 square foot facility on a site covering more than 40 acres.
    This all new facility will produce the majority of Suzuki two-wheeled products for U.S. distribution. The site of the facility was chosen in part due to its geographically desirable location and proximity to Suzuki headquarters.
    Suzuki also operates an All-Terrain Vehicle assembly plant in Rome, Georgia.  Active since 2001, Suzuki Manufacturing of America (SMAC) exclusively builds Suzuki’s award-winning line of utility-focused ATVs for worldwide distribution. Suzuki launched all-new versions of its KingQuad 750 and KingQuad 500 in May.
    Source: Suzuki Motor of America, Inc.

    Kevin from Wiseco
    When it comes to overall strength, there's no beating a forged piston. But what is the process that yields the toughest parts in the racing world? We'll show you. 
    When it comes to turning raw metal alloys into useful things, two processes dominate - casting and forging. Both have their place, but when strength and light weight are priorities, forging is the method of choice. Though it’s been around for more than six millennia, forging processes continue to advance the state of the art, bringing us everything from sharper, more durable kitchen knives to more fuel efficient jet engines, plus things much closer to our heart: lighter, stronger pistons.

    Although forging is a metalworking process thousands of years old, it’s still the best method to produce components with the highest strength and durability.
    Forging is defined as the controlled deformation of metal into a desired shape by compressive force. At its most basic, it’s a blacksmith working a piece with a hammer and anvil, and those first metalworkers toiling at their forges discovered something important about the pieces they were crafting – compared to similar objects made from melted and cast metal, they were stronger and more durable.
    Though they knew the finished product was superior, what those ancient smiths didn’t suspect was that the act of forging was changing the internal grain structure of the metal, aligning it to the direction of force being applied, and making it stronger, more ductile, and giving it higher resistance to impact and fatigue. While a cast metal part will have a homogeneous, random grain structure, forging can intentionally direct that structure in ways that give a finished part the highest structural integrity of any metalworking process. 
     
    Wiseco forged pistons start as raw bar stock in certified 2618 or 4032 aluminum alloy. Once they’re cut into precisely-sized ‘pucks’ they’re ready to be preheated in preparation for forging.
    Although many performance enthusiasts might put billet parts at the top of the heap in terms of desirability, the reality is that the billet they are created from doesn't have the same grain properties of a forging. 

    The Wiseco Forging Process
    Today’s state of the art in forging technology is far removed from the smith’s bellows-stoked fire and anvil. In Wiseco’s ISO 9000-certified forging facility, pistons begin life as certified grade aluminum bar stock, cut to precise lengths to form slugs. The choice of material is critical - conventional wisdom has always said that a forged piston requires additional piston-to-bore clearance to allow for expansion, leading to noise from piston slap until the engine gets up to temperature, but per Wiseco’s Research and Development Manager David Fussner, “Forged pistons do require additional room temperature clearance. However, the 4032 forging alloy we use has about 12% silicon content, and this significantly controls the expansion to nearly the same as a 12% silicon cast piston. The 2618 alloy expands a bit more and does require a bit more room temperature clearance than 4032.”

    Pistons are forged in a ‘backwards extrusion’ process where a moving punch presses the raw material into the die to form the rough shape. The process takes only a fraction of a second (longer in the isothermal press), and the speed of the press helps determine how material flows, and therefore the internal grain structure of the forging.
    While 4032 is more dimensionally stable across the typical operating temperature range seen inside an engine, it does give up a small advantage in ductility to 2618, which has a silicon content of less than 0.2 percent. This makes 2618 a better choice for applications where detonation may be an issue, like race engines running high boost or large doses of nitrous oxide. The low silicon alloy’s more forgiving nature in these instances makes up for the tradeoffs in increased wear and shorter service life compared to 4032.
    Once cut to the proper size, slugs are heated to a predetermined temperature and moved to the forging press itself, which is also maintained at a controlled temperature. There are two different types of presses employed at Wiseco; mechanical and hydraulic. Both have a long history in manufacturing, and each has specific strengths. Mechanical forging presses are well-suited to high production rates, helping to keep the overall cost of high-quality forged components affordable. Hydraulic presses have the advantage of variable speed and force throughout the process, allowing greater control of material flow, which can be used to produced forged components with even more precisely controlled physical properties.

    Wiseco’s isothermal hydraulic press forging machines use precise digital control of the temperature of the raw material, the punch, and the die, as well as the pressure exerted during the full motion of the forge. This allows very close control over the physical properties of the finished forging.
    Regardless of the type of press, pistons are forged using a “backwards extrusion” process where the material from the slug flows back and around the descending punch to form the cup-shaped forging. Picture the stationary part of the press (the die) as the mirror image of the piston top, and the punch as the mirror image of the underside. As the punch descends, the puck is transformed into the rough piston shape with material flowing up along the sides of the die and punch to form the skirt. This entire process takes place on the scale of milliseconds (on the mechanical press), and the all-important flow stresses of the material are determined by the strain rate (or speed) and load applied by the press.
    In addition to three mechanical forge presses, Wiseco also has two isothermal hydraulic presses in-house. These state of the art forges maintain the temperature of the piston slug, the die, and the punch very accurately through computer control, delivering more precise dimensions and geometry for the finished pieces, as well as allowing for more complex designs to be successfully forged, and even the creation of metal matrix composite forgings.

    Once the puck (left) has been transformed into a forged blank (middle), it still has a ways to go before becoming a completed piston (right).
    The Heat Is On
    Once the forging process is complete, the components next move to heat treatment. Wiseco’s aerospace-grade heat treatment facility is located in the same plant as the presses, and here the pistons go through a carefully controlled process of heating and cooling that relieves stress induced during forging, increases the overall strength and ductility of the metal, and provides the desired surface hardness characteristics. 
    While casting can deliver parts straight out of the mold that are very close to their final shape, forgings require a bit more attention in order to get them into shape. Fussner explains, “In a dedicated forging for a specific purpose, the interior of the forging blank is at near-net as it comes off the forging press.  And in some cases, we also forge the dome near-net with valve pockets and some other features. Other than these items, most other features do require machining.”

    Pistons aren't the only thing Wiseco forges and machines in-house. Wiseco clutch are also forged and machined, as well as finished with hard anodizing. The forging (left) allows the basket to closer to the final shape before machining. The basket shown here is just post-machining.
    One basic forging may serve as the starting point for many different types of finished pistons, unlike castings which are typically unique to a single design or a small group of very similar designs. Regardless of the manufacturing method for the piston blank, some degree of final machining needs to take place to create a finished part. “As a ballpark percentage, I would say about 75% of the forging blank would require machining.” Cast pistons also require finish work on the CNC machine, but this is almost always less extensive than a similar forged piston. “That’s the main reason why forged pistons are more expensive than a cast piston,” Fussner adds. 
    Another reason for the added expense of forging is the significant cost of the initial tooling for the die and punch, which must be made to exact specifications and be durable enough to survive countless forging press cycles. Per Fussner, “We control these costs by making all our forging tooling in house at Wiseco headquarters in Mentor, Ohio.” The ability to make their own tooling, doing their own forging, and their in-house heat treatment facilities make Wiseco the only aftermarket forged piston manufacturer in the United States with these unique capabilities.
    Once the machining process is complete, Wiseco pistons can also receive a number of different proprietary coatings to fine-tune their performance. These include thermal barriers as well as wear reduction treatments.
    Though forging is a technique literally as old as the Iron Age, it’s still the undisputed king of manufacturing techniques for light, strong, durable components. Wiseco continues to refine the process with the latest methods, materials, heat treatment, and machining to provide the highest quality aftermarket components available, at an affordable price.

    Wiseco forged pistons provide superior quality and performance at an affordable price thanks to the company’s close control over every step of the manufacturing process.
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