Jump to content

Kevin from Wiseco

TT Sponsor
  • Content Count

    48
  • Joined

  • Last visited

2 Followers

About Kevin from Wiseco

  • Rank
    TT Member

Profile Information

  • Gender
    Male
  • Location
    Ohio

Recent Profile Visitors

1,959 profile views
  1. Kevin from Wiseco

    Single-Ring vs. Two-Ring 2-Stroke Pistons: Which One is Better?

    Yes, you would have to keep the top ring. But it's always recommended to only run them as they were designed. It would only be recommended to buy a single-ring piston specifically if that's what you're looking for.
  2. Single and dual compression ring two-stroke pistons have been in service for decades, and since their inception, many have wondered if there are advantages to one or the other. If you have been involved with dirt bikes, jet skis, or snowmobiles long enough, you’ve probably noticed different manufacturers have chosen to use one or two compression ring piston designs for their engines. Furthermore, you may have noticed some aftermarket piston companies offer single ring pistons that replace dual ring pistons and vice versa. So, as a consumer, what do these design differences mean, and which one should you choose? Wiseco has been manufacturing two-stroke pistons since 1941. In fact, the company started with two-stroke racing pistons being built in Clyde Wiseman’s garage. There’s no replacement for experience, so we want to take this opportunity to shed some light on the advantages and disadvantages of single and dual compression ring two-stroke pistons designs. Compression Ring Function We’ll start with a quick review of what a compression ring is designed to do. First and foremost, the compression ring provides a seal that allows the piston to compress the air/fuel mixture as the piston travels upward, then during the combustion event itself, it seals the rapidly expanding hot gases that form during the combustion event. The effectiveness of the compression ring seal, in part, has a significant effect on the power and efficiency of the engine. Should the compression ring lose its ability to seal, the amount of trapped air/fuel mass that will be retained during the compression stroke will be significantly reduced, resulting in less power. Similarly, during the combustion event, a compromised ring seal will allow more gases to leak past the ring, often referred to as blow-by, resulting in reduced power. The compression ring, or rings, seals compression so the piston can compress the air/fuel mixture. This plays a critical role in performance, as an improper seal will cause a very poor running condition or not allow the engine to run at all. Heat Transfer The piston rings play a vital role in transferring heat from the combustion process to the engine's liquid or air cooling systems. During combustion, the piston crown absorbs a portion of the extreme temperatures it is exposed to. If left unregulated, the piston would become so hot that it would melt. Thankfully, the piston rings transfer heat from the piston by connecting the piston to cooler parts of the engine such as the cylinder liner. From the liner, the heat finds its way to the water jacket or to the cooling fins on an air-cooled engine. Engine designers optimize the size, shape, position, and the number of rings to influence how the piston and rings transfer heat. In addition to sealing compression, the piston rings play an important role in transferring heat from the piston crown and through the cylinder wall to be dissipated by the cooling system. Otherwise, the piston material would not survive the extreme heat. Conformability The piston ring’s conformability refers to how well it adheres to the shape of the cylinder bore. The conformability of the ring will have a direct effect on how well it seals the mixture and combustion gases as well as transferring heat to the cylinder liner. Factors that influence a ring’s conformability are shape and thickness. In particular, thicker rings will be less conformable than thinner rings because ring thickness has a significant influence on ring stiffness. Thicker rings are generally less conformable, and therefore may not seal compression as effectively. However, too thin of a ring will not transfer heat well enough. It's important to develop a balanced ring that performs both tasks effectively. Wiseco’s Research & Development Manager comments, “Racing applications tend to favor single rings for a lower friction penalty. Also, thinner single rings have better conformability to the cylinder and are less susceptible to flutter at high RPM. Even when specified with lower tension, thinner rings can still have good unit pressure which promotes sealing without a high friction penalty.” Single Versus Two-Ring Applications While many have speculated that certain types of two-stroke powered vehicles—whether it be ATVs, dirt bikes, jet skis, or snowmobiles—need one or two ring pistons, it isn’t so much the specific vehicle application that drives the selection, but more the intended use for the vehicle. The big differentiator is whether the vehicle’s intended use is for racing or not. Two-stroke engines designed and developed for racing typically utilize single ring pistons. When designers optimize an engine for racing and select a single compression ring design, several advantages and disadvantages arise when compared to a two-compression ring design. Let’s take a look at the pros and cons of each. A single-ring design is common among Wiseco pistons that are designed for racing and high-performance engines, such as the Racer Elite piston. Single Ring Pros: ● Lowest friction design translating to increased power ● Lowest weight design contributing to fast revving Single Ring Cons: ● Potentially less longevity due to heat dispersion Two-rings designs are popular among riders that prefer added performance durability at the expense of a little performance. However, some big-bore two-stroke applications benefit more overall from a two-ring design. Two Ring Pros: Improved heat transfer due to the addition of the second ring Engine performance durability due to 2nd ring’s ability to seal if first ring’s seal becomes compromised Two Ring Cons: Increased friction and weight More susceptible to ring flutter at high RPM “Since a good portion of the piston heat is transferred from the piston to the ring and then to the cooler cylinder wall, one advantage of a 2-ring system is that the second ring would provide a second heat transfer path,” adds Dave Fussner on the topic of two-ring designs. The last point worth mentioning is that racing piston ring applications are optimized for excellent ring control at high RPM. A condition called “flutter” occurs when a ring becomes unseated from the piston’s ring groove. Flutter occurs around top dead center as the piston transitions from upward motion to downward motion, in part, because the inertia of the ring, which is a function of the ring’s mass, overcomes the gas pressure, pushing the ring against the bottom of the ring groove. When this happens, the ring’s sealing ability is compromised, and engine performance degrades both in terms of performance and durability. Engine designers combat flutter by optimizing the ring's weight so that the ring’s inertia forces cannot induce flutter within the intended RPM range. This is why in many single ring applications the rings are relatively thin. Single-ring designs are less susceptible to flutter because there is less ring mass changing direction as the piston begins its return from TDC. These are the general and major factors that drive single ring and two-ring designs in two-stroke pistons. The intended use of the vehicle usually drives ring selection, not the vehicle type itself. If you are considering a switch from a single ring to a two ring piston, ultimately, how you intend to use your machine should dictate whether the decision is sensible or not.
  3. Kevin from Wiseco

    Wiseco's New Garage Buddy Steel Valve Kits

    We do offer replacement steel valves for them currently, but we don't yet have them kitted to include springs as well.
  4. Kevin from Wiseco

    Wiseco's New Garage Buddy Steel Valve Kits

    Glad to hear they've held up well! Yes, our valves are still manufactured in Japan by OE suppliers, so we're able to provide the confidence of Japanese steel.
  5. With a little bit of work on your part, Wiseco Garage Buddy Steel Valve Kits can help your dirt toys deliver years of service. Read on for full details on these reliable and affordable valve replacement kits. One of the basic truths of the imperfect world we live in is that the people who design machines are not the same people who have to maintain those machines. This often leads to situations where something that seemed like the way to go on the CAD screen turns out to be more difficult or more expensive to fix in the real world than it otherwise would be. Exotic materials and painstaking processes that are economical to implement when you’re mass-producing something turn out to be expensive to service in the field. Today's 4-strokes are engineered to be high-tech, but the parts come with a big price tag. In this single-serving, throw-it-away-when-it-breaks world, there are some noble souls who take a stand and say that we should be able to service and maintain things ourselves instead of discarding them, bringing new life to machines that need a bit of a refresh. Such is the case with Wiseco’s Garage Buddy Steel Valve Kits for a variety of popular dirt bike and ATV applications. Wiseco Garage Buddy Steel Valve Kits were engineered to be a more reliable and affordable option for riders who need to replace valves in their modern four-stroke machines. Read on for complete details! When faced with the price tag on factory replacement parts for bikes that came with trick valvetrain components, many owners cringe at the price of refurbishing a tired engine. However, with the right components at the right price, turning your dirt bike’s mid-life crisis around and letting it catch its second wind can be easy. Win on Sunday, Sell on Monday With the incredibly impressive machines under race tents worldwide, nobody wants to buy a new bike that has a whiff of “outdated” technology surrounding it, so a lot of the high-end features that really only make a difference to the top one percent of professional racers become must-haves for weekend warriors who just want to trail ride with their kids. When those parts wear out, the exotic bragging rights come with a cost, though. “Titanium is a great valve material due to the strength-to-weight ratio, and also the material’s ability to deal with the high temperature of combustion,” Wiseco Product Manager Dave Sulecki explains. “The light weight is important for engine acceleration; imagine how a heavy component takes more energy to move, and you can see where titanium is ideal when the camshaft needs to accelerate the valve quickly with less energy, and you can see that a lightweight component would be critical for a high-end racing engine.” Titanium is popular for valves for its light weight properties, but they are expensive to manufacture and can wear out faster than steel. While those race-spec valves come standard because they’re a positive selling point on the dealership floor, they’re mostly there for bragging rights instead of making a difference you’ll feel when twisting the throttle yourself, and it’s cheaper for the manufacturer to make everything to one specification than it is to have separate designs. “This light weight and performance comes at a greater cost,” Sulecki adds. “The material is more expensive, and costs more to machine or form into a valve. Additionally, the titanium requires a special coating to deal with the heat and wear, which also adds cost. This expense is needed for the highest performing engines, like the type you find in nearly all levels of racing from motocross up to Formula 1.” Sticker Shock Even expensive, exotic materials wear out, though, and when it’s time to freshen up the valvetrain of your bike, you might be surprised to see just how much it will cost to replace like-for-like with factory components. Per Sulecki, “Steel valves are a great low cost alternative to titanium, and offer longevity, reliability, and improved wear over titanium. Some customers are not always racing their vehicles, and just want longer service intervals and the peace of mind that comes with this material.” "Steel valves are a great low cost alternative to titanium, and offer longevity, reliability, and improved wear over titanium." - Dave Sulecki, Wiseco Powersports Product Manager That’s where Wiseco’s Garage Buddy Steel Valve Kits enter the picture. They’re designed to be an affordable way to refresh your high-tech dirt bike’s valvetrain. Although they may not be made from titanium, that doesn’t mean they aren’t precision-engineered. “Because steel valves are a small percentage heavier than titanium valves, heavier-rate valve springs are required to control the valve and protect the engine from valve float (the condition where the heavier valve will stay open under high RPM engine speeds),” Sulecki explains. “These springs are included with the Garage Buddy Steel Valve Kits.” Garage Buddy Steel Valve Kits are available separately for both intake and exhaust valves. They come complete with the valves, springs, and even a free packet of cam lube to make sure every box is checked during your reassembly. Converting to steel valves requires using valve springs designed for the specific weight of the valve. Springs are included with Garage Buddy Steel Valve Kits. Wiseco’s extensive experience with powersports valvetrain components provides confidence that their conversion kits are engineered to restore showroom-floor performance, and they utilize stock retainers, seals, shims, and other components for affordability and drop-in compatibility. The springs are crafted from premium chrome vanadium steel, and the nitrided steel valves can actually outlast an OEM titanium valve by a factor of three or more. Wiseco's nitrided steel valves are designed to utilize stock retainers, keepers, and seals. The steel conversion valve springs are manufactured from chrome vanadium steel. Time For A Change So, how do you know when it’s time to replace the stock components, short of a dropped valve or broken spring? Per Sulecki, “Valves and valve springs wear over time, like any highly-stressed engine component. When you are checking the valve clearance, or making shim adjustments, this is always a good indicator how quickly the valves are wearing or receding into the seat.” Keeping an eye on these telltales during your regular maintenance will allow you to judge when your factory valves and springs are reaching the end of their service life. Entire engine in need of a refresh? Garage Buddy also offers Complete Engine Rebuild Kits, check them out here. “When you are inspecting your top end for general overall health, such as the piston and ring condition, this is the best time to take a closer look at the valves and valve springs,” he continues. “Valves and springs need to be removed from the cylinder head for full inspection. Once these are removed, you can look closely at the condition of the valve face where it seals to the valve seat, and also the condition of the valve head overall and the stem condition. Any cupping or damage to the valve face means it is time to replace the valve, and any similar wear to the valve seat means replacement or re-cutting will be needed.” Inspecting your valves for wear while doing a top end is a good idea. Closely inspect the sealing surface of the valve for cupping, and inspect the rest of the valve for wear or damage. It's a good idea to also check the groove at the top of the stem for signs of wear to avoid breakage. Over time, springs become less elastic and may no longer be able to control valve motion at high speeds, but it’s not the sort of wear that is immediately obvious to the naked eye. Sulecki suggests, “Valve springs should be inspected for free length, and also overall condition, looking for any wear marks or defects that can lead to spring failure.” Any nicks or cracks are a sure sign of impending doom, and your cue to replace the entire set. Valve spring free length can be measured and compared to the recommended spec to get an idea of wear on the spring. Doing the Job Right Depending on your level of mechanical aptitude and how well-equipped your garage is, valve replacement might be a job you want to subcontract to a professional. “For most all valve replacements, it is a good idea to work with a qualified builder if you are not sure about the condition of any of these components,” Sulecki suggests. “The work can be done in your own workshop, but there are some special tools required to remove the valves from the head, and having an experienced eye on these items is always the best approach if you are not sure what to look for. An OEM service manual is always the best place to start, they will provide information about any special tools, and guidelines of what to look for regarding valves, valve seats, and even valve guides, and their condition.” When replacing your valves, be sure to use proper tools and follow all procedures and specifications outlined in your owner's manual. If you're unsure about performing your own valve maintenance, we recommend taking your machine to a trustworthy and certified shop. Whether tackling the job yourself or letting a pro handle your top-end maintenance, you’ll save time and money by seeing to all the wear-prone components at the same time. Sulecki adds, “When replacing valves, it is a good idea to inspect the top end for any concerning issues or conditions. Inspect the valve seals, valve keepers and seats, shim buckets, the condition of the cylinder head (flatness and sealing condition), and cam chain condition.” Needless to say, the time to service or replace these components is while everything is apart in the first place, and by using quality components like Wiseco’s Garage Buddy Steel Valve Kits, you’ll protect your investment for many off-road seasons to come. Wiseco Garage Buddy Steel Valve Kits are available separately for both intake and exhaust valves.
  6. Kevin from Wiseco

    Wiseco's Two-For-Two-Stroke Rebate

    Thank you!
  7. Kevin from Wiseco

    Wiseco's Two-For-Two-Stroke Rebate

    Thanks for the heads up! What part number piston did you use and what model Beta do you have?
  8. Kevin from Wiseco

    Wiseco's Two-For-Two-Stroke Rebate

    We're glad you love it! Thanks for the support! Thank you for the longtime support!
  9. Attention two-stroke riders! For a limited time, Wiseco is offering to let you choose up to two FREE items with proof of two-stroke piston(s) purchase! Read on for all the details on this offer. Who doesn't love the sound, smell, and fun of a two-stroke? Wiseco has a new rebate offer just for the two-stroke lovers! For a limited time, Wiseco will be offering your choice of up to TWO (2) different free items with a minimum purchase of any off-road bike or ATV Wiseco two-stroke shelf piston(s)! Choose from our new high-quality, modern-fit Wiseco T-shirts, the new Wiseco Patch hat, or a top end gasket kit! Simply pay a flat $10 shipping fee. Click here to go to the Two-For-Two-Stroke rebate form! How does the rebate work? To participate, follow the instructions below. Purchases must be made between TWOsday August 28th and TWOsday October 30th, and redeemed by November 30th. Purchase a minimum of $118 of any new off-road bike or ATV Wiseco two-stroke shelf piston(s) for ONE (1) FREE item, or a minimum of $165 for TWO (2) FREE items. Save your receipt/proof of purchase and piston box. Scan or take a photo of the proof of purchase and the piston box label showing the part number, and upload to the online rebate form. Click here to go to the online rebate form, fill it out completely with all required information, be sure photos from step 3 are uploaded, and submit. Allow 1-2 business days to be contacted by a Wiseco representative, pay a flat $10 shipping fee, and allow 4-6 weeks for your free item(s)! This is an example of the piston box label you will need to upload a photo of. The free item options include our new, high-quality modern-fit T-shirts! Click here to find Wiseco two-stroke pistons for your application! All Wiseco two-stroke pistons are forged in-house for added strength and durability, and are available for wide variety of applications. Wiseco Two-Stroke Racer Elite Wiseco's latest development in two-stroke piston technology is the Two-Stroke Racer Elite piston. These pistons are forged from a 2000 series alloy for additional strength qualities, and protected by Wiseco's ArmorPlating coating on the piston crown and in the ring groove(s) for long-term protection from corrosive combustion chamber conditions. Watch the video and get the complete details on Two-Stroke Racer Elite HERE. Don't forget! Some two-stroke pistons require exhaust bridge lubrication holes to be drilled in the piston, and the exhaust bridge on the cylinder to be relieved. Not sure if you need this, or need help completing these tasks? We explain it all HERE. Do you know the importance of exhaust bridge relief and lubrication holes? Review our full explanation here! Check out some more of our awesome two-stroke content! Dirt Bike Mag YZ125 Build 80+ HP Two-Stroke Karts Wiseco Employee-Built 390cc TRX KTM TPi Two-Stroke Pistons What is a Locating Pin? Wiseco "Two-For-Two-Stroke" Rebate Terms & Conditions Purchase at least $118 worth of any offroad bike or ATV Wiseco two-stroke shelf piston(s) from any dealer or retailer between August 28, 2018 and October 30, 2018 and receive your choice of one out of four available items, or purchase at least $165 under the same stipulations above for your choice of two out of four available items, after online form submission. When applicable, two chosen items must be different, one item cannot be doubled-up. Wiseco two-stroke piston kits and PK kits eligible. Purchased dollar amount minimum must be met completely by Wiseco two-stroke piston product. $10 shipping fee applies to free items. Final shirt and hat colors and designs may not exactly reflect items pictured in promotion images. Promotion does not apply to custom pistons. Minimum purchase amounts at retail value only. Rebate form must be submitted electronically at www.wiseco.com/promo with all required information. Must provide photos or scan of proof of purchase and piston box label showing part number. Allow 4-6 weeks to receive your chosen items. Offer must be redeemed by November 30, 2018. Offer good only in 48 contiguous states. Limit one rebate per eligible purchase, per household. Maximum number of free items is two. Free gasket kit limited to a retail value of $69.00. P.O. Box address not accepted. Must be 18 years of age. This rebate offer is valid for end consumers only and not available to distributors, dealers, resellers, retailers or e-tailers. Offer void where prohibited, taxed or restricted by law. Please keep a copy of your submission. Substitution of products not valid. Qualifying products cannot be returned to the retailer once the rebate form has been submitted. Offer has no cash value. No substitutions. Void where prohibited by law.
  10. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    Thank you! We were on the same page with the transmission bearings, we figured most people would not need them, so it would be better to keep the price point more affordable for people and not include them. We're glad to hear you've good experiences with the cranks, we've been working hard for that!
  11. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    The only valve train components included in the 4-stroke kits are cam chains, but there are no valves/springs, etc. However, keep your eye on us, because you may see something you're looking for coming soon. 😉
  12. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    Thank you for noting interested in this model, I'll make sure the interest is known internally!
  13. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    KX250 is on the list as well!
  14. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    Update: The crankshaft is on the list of to-dos, but it would most likely be next year sometime before we see a Garage Buddy kit for it.
  15. Kevin from Wiseco

    Wiseco's Garage Buddy: Complete Engine Rebuild Kits for Dirt Bikes!

    We haven't seen as a high of a demand for bottom end rebuilds on those models, but I can check in with the Product Manager to see what the timeline looks like.
×