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Found 44 results

  1. I'm looking at picking up a used DR650/KLR/690 Enduro for the lady friend and there happens to be a cheap DR650 in my area for sale right now. The potential problem? It's a model year 2000 with less than 4500 miles on it. I have a 2013 DRZ-S that has about 6000 miles on it and I feel like that's borderline neglect so a 2000 with even less has me concerned. What should I look for or be concerned about that I can check in someones driveway. Would it be worth it to trailer it somewhere and have it checked out professionally? I'm new to the area and therefore don't have a "trusted mechanic" and the nearest Suzuki dealer is ~2.25 hour drive away. Edit: I should add that I've got probably 30 hours seat time on a 2007 DR650 so I know roughly how they should feel.
  2. Hello all, I know this is a highly debated topic and one that has probably been discussed at great length. I apologize in advance for opening up this can of worms. Unfortunately, when I have done searches both on this forum and google, virtually all the threads I have read are old (2004-2010, maybe 1 thread from 2011'). I have not seen anything (2013-2017) regarding this topic. I think with progression of engineering that reliability on both 2 strokes and 4 strokes on 2014 + bikes is vastly superior of that of 2004-2010 bikes. (maybe I am wrong....) My background: I had a Yamaha RT 100 and TTR 125L back in the day (my only dirt experience). Then ended up with a GSXR 750 after college, then a KTM 690 SMC supermoto, CBR 600 track bike, and then a Husqvarna 701 Supermoto. So I am not new to motorcycles but my knowledge of dirtbikes and dirt riding is pretty limited. Obviously coming from a street bike the maintenance and service intervals are substantially different than a dirtbike. Hell, even my track bike does not require all that much maintenance and I ride the crap out of that (change oil every few track days). I want to get a dirtbike that I can go ride some trails (I will probably just putt around) and occasional try and ride a MX track (I imagine I would be very slow. I road a MX track back with my TTR 125L but that sucked because it had no suspension- amongst other things). So while I do not need race bike power, I would like suspension capable of hitting some MX jumps. Hence why I do not want a trail bike like a TTR 230 or CRF 230. I want something that would be able to actually take some jumps if I get to that point (I at least want to try and progress to that point). My question is: Would a 2 stroke (no older than 2007') be easier/cheaper to maintain than a modern day 4 stroke (2012' +). I have read 2 strokes need a top end rebuilt every 20 hours. Some say 30 hours, and I have heard people not racing run 2 strokes for 60-80 hours without a rebuild. Then they say 4 strokes are full engine rebuilds when they go (and the cost of the actual pistons and rods are significantly higher on the 4 strokes?) I will be riding not nearly as hard as many people on here would. I understand the powerband difference and all of that. I am more concerned with wrench time and cost to ride over anything. P.S. Holy crap, people have their bikes overpriced on craigslist. I am trying to pick up a small bike for my fiance and I am seeing like 2004-2007 TTR 125L's for like $2,000- $2,200..... a 10-13 year old small displacement trail bike???
  3. Hi, brand new to this forum so excuse me if this is in the wrong section! We got a 2002/03 (unsure), yz85 a couple of months ago. Very few issues at the start, ran perfect. In the past two months the bike has been very temperamental. It was idling very high when it started but alot of the time it wouldnt even start. Was making very throaty, burpy kind of noises, especially with a bit of a throttle twise to try and get it going. So, after pulling the carb to bits, cleaning all of the jets, itd run once well, then do the same thing again. We repeated this process 4/5 times to date. We eventually routed the cause to a frayed intake boot causing a vacuum leak. So we replaced it. Good as new. For the first run.. kicked like a horse the first time we ran it after replacing the boot. Then today, she's back to her old self. Started fine earlier, and then just went throaty and started to die. Sounded like the plug wasn't firing. So took it out, checked. Nothing, check if there was power to the coil pack, got a spark, so cleaned the plug with a wire brush (b10eg, btw) Away she goes again, for 2 minutes, and dies. Back to making throaty sounds again. The plug is working as of now. The bike would start if the throttle was wide open but be very very throaty, burpy and rough. Carb was cleaned earlier before this. (Today) That's all the detail I can give, any questions feel free to ask me. I've given up on it as I'm all out of ideas. There was a bit of black oily stuff leaking out of the exhaust as well, only noticed as I was finishing up. Any help, ideas, suggestions are welcomed. I have a video of it but can't upload here. Thanks in advance
  4. Hey Guys, I bought a 2012 CRF450R around 8 months. I decided to get back into riding after my Dad bought my son a CRF50 for christmas. I was following him around on my XR100R and was having a blast, but came across a cherry 2012 crf450r for sale by an older gentlemen that claims he rode it a few times a year and was meticulously maintained. The bike runs great (in my opinion?) and is stock other than a clutch lever, shifter, and Racetech Gold valves. Anyways had a family emergency that led to the bike sitting for over 8 months with 3/4 tank after only riding it for about an hour since I bought it. I fired it up a couple weeks ago after a couple kicks and seems to be fine. I have searched through the forums and found some info on draining the tank, but mentioned the tank was pressurized and needed a special honda tool to re-pressurize. What is easiest way to drain the fuel and do I need special the tool? Or since the bike fired up and seemed to be running okay in the neighborhood, just burn through the tank? Or could this cause damage? I have a service manual coming in the mail from ebay as I plan to learn to do my own bike maintenance and havnt performed a proper check of everything since I bought it, but was hoping I get some help while I wait for snail mail. Thanks for putting up with newbie crap. Much appreciation!
  5. I just bought an '03 CRF230F and am eager to start riding it and getting used to it. I've ordered the official Honda Service Manual but it won't be here for up to a week. I want to change the engine oil on the bike ASAP though. Can someone tell me what weight oil to use? Thanks, and I'm looking forward to participating in these forums!
  6. I am buying a used 2014 300xc from a local seller. I am looking for some advice on the initial maintenance that I should perform after picking it up. Background: His dad bought it new in 2014, selling it to him in 2016. He is selling it to upgrade to a 2017. The seller raced recreationally in some local enduros. The motor is untouched. Never rebuilt top or bottom. (seller said he guessed 70 hours, but I assume it's much more) It has a bent radiator (not leaking). New pipe. New Silencer. Says he just replaced the clutch pack, chain and sprockets. The bike looks heavily used, but for agreed upon price I am happy with it. What are the must do maintenance items I should perform before riding in the spring?
  7. Hey TT, I just got 2005 DRZ400E. It didn't come with any manuals that's why I'm asking fellow DRZ owners for some help. Please bear with me if I'm asking obvious and or lame questions, it's my first bike . I'm in Colorado @5280' plan to take it to higher elevations. My riding will be some pavement and the rest FSR's, maybe some super easy single tracks initially. I plan to plate it. What manual, including repair manual, can be recommended? Anything available to download? I found a manual on DRZ400E.com but it seems to be for the S model and not the E. What gas should I use? It's a higher compression motor and I believe the manual calls for 91. Although, would it be different at a higher altitude? What oil and filter should I use? How ofter should I be changing oil? What air filter and sealant is recommended? What hand guards do you recommend? Integrated turn signals might be nice but not a deal breaker Skid/bash plate. Security. It's stored in the garage most of the time but I might need some extra security when I travel. Here are some things I thing might be useful. Any thoughts? Front disk break lock with alarm Heavy duty chain and a lock Speedometer. It just came with a trip meter. What break fluid can be used? What coolant should I user? Any cool taillight hubs? Front and rear tires. I'm thinking of getting Kenda Trackmaster II K760 as they appear to be a good bang for the buck. Are Dunlop D606 that much better as the price suggests? Mirrors. Something neat would be nice.
  8. Recently got this bike and it was pretty neglected by previous owners. I decided to do some maintenance due to the fact that I broke my wrist. I noticed trying to replace the fork seals and bushings that the left side damper compresses and stays compressed fully while the right side pushes in and back out. Any reason as to why? Also the bushings on the dampers are different on both sides. Is that normal?
  9. Hello fellow 2020 KLX300R owners, I hope you're having a good day. I am planning on purchasing a 2020 KLX300R of my own but before I do, I need to know about maintenance intervals. I know that the less powerful KLX230R is pretty much "bulletproof" in terms of reliability if you keep up with engine oil changes, cleaning the air filter, and lubricating the chain. The 300R is much more different though since it has 4 valves instead of 2 on the 230R, liquid-cooling as opposed to air, and a DOHC compared to a SOHC. How does this affect maintanence and reliability? Is the regular oil change, filter clean, and chain lubrication enough? Thank you!
  10. Hello fellow 2020 KTM 150 XC-W TPI owners! I am debating on whether I should purchase this bike over something else in the price bracket such as a YZ250FX. I am currently more interested in the 150 since it is lighter, potentially more fun/engaging, and the fact that I have never had a two-stroke before and would like to indulge in owning one. My main concerns though are maintenance and reliability. Since the TPI system is new for the 150, I don't know if it's financially applicable to purchase a bike with since it may be prone to failure. What I would helpful is if you could post your personal experience with KTM's TPI (specifically on the 150 XC-W if possible). Also, how does this system affect general two-maintenance such as top-end builds (how many hours I can put on a single top end with normal riding for a small bore two-stroke) and what kind of extra work is required to maintain the components that the TPI consists of? In addition to this, does the fuel injection system increase the wear of specific engine parts such as the piston or cylinder? Responses to these questions would be great! Thank you.
  11. I'm almost 17 and looking at getting my first dirt bike, not too powerful or expensive. Where I live there's only (at the moment) one CRF 150F for sale versus a lot of 150Rs. From what I have heard the 150F is way more reliable and cheaper to own. Is it actually a big difference or should I just get a 150R if I can't buy the 150F? also the bikes I've looked at are 2005-2006 around 1200-1400€.
  12. Hey- was doing some work on my xr100 and dropped a socket between the engine and frame. it is in a tight spot and i cannot get it without removing the engine. Is it ok if i just leave it in there? will it break anything? thanks!
  13. Hello fellow riders, Being a dual-sport fan by heart and a software developer by trade, I couldn’t resist the urge to create an app that would help me to keep track of my bike’s upcoming maintenance schedule, service history and expenses. Initially created for my Suzuki DR650 and available to the DR650 community, I just had to extend it to support the mighty Honda XR650… not after months of nagging from a XR650 friend (hello Nick, I know you’re reading this). Free forever, no ads, no bs! Android only, sorry iPhone users. Don’t take my word for it, link: get it on Google Play Store Your feedback is welcome and appreciated. Have fun riding!
  14. New to dirt bike riding and need to service forks and replace fork seals. I have air bleeders buttons on my fork caps. To use the fork cap tool I'll need remove them when I tighten down the cap to the damper assembly. My question is will I have a problem with oil trying to come out the air bleed or air getting in when I have them out reassembling the damper together. Or do I need to buy oem air bleed screws. Thanks
  15. I live in the PNW and this week we have had enough rain to last 6 months. I just picked up a very low hour 2011 CRF and have been going through the bike methodically changing fluids, greasing, and lubing getting it ready for the season. If you’re bored I suggest you do the same thing. If you haven’t greased your bikes linkage and steering head that will take the better part of an afternoon. Might was well do the forks while they’re off. How about putting anti-seize on the chain adjuster bolts? Having one of those stuck in the swing arm will ruin your day. If you’ve been neglecting maintenance I suggest you get on it. Spring is coming my friends!
  16. I've read here and there about regular greasing and lubing on the YZ250 / YZ250X, as well as noted the recommendation in the manual (same manual for both bikes, see image), though I do not think it consolidates all of the grease and oil points into one checklist, hence this post. As a sort of newbie getting back into dirt bikes after a long time (as a kid I only fixed things after they broke), plus being new to the YZ250 platform, I'd appreciate any suggestions one what you grease or lube and how often (and maybe even with what product). Thanks!
  17. Hi I recently bought a yz125 and I'm very new to the sport but I'm not very sure on what good air filter maintenance takes. First off I took off my air filter and it looks pretty dirty compared to the clean rim. If it needs to be cleaned what do I use to clean it? I have cleaned air filters before but not on my own so I know a little bit of what to do. Anything helps thanks.
  18. Hi All, I'm a new to the bike, it's a 2010 450 RR. I'm looking to change to Evans waterless coolant. (Side note: I'm hoping it'll run a little cooler.) I'm not sure where the drain bolt is. Can anyone tell me where to find it? Thanks, Chris.
  19. Hello, I feel like I have read all the tips and tricks on the spongey/springy KTM front brake. I've got an 05 250 EXC and last summer I lost my rear brake during a ride, so I decided to do some maintenance this winter on both front and rear. Rear brake went smooth, new pads, rebuild kit on mc and caliper, fresh fluid, new lever bearings. Rear brakes now work great, but the front brakes are spongey/springy. I've tried just about everything from zip-tie to tapping on the caliper when bleeding, back bleeding with a syringe and traditional bleeding. What I am noticing now is, my lever gradually gets firm as it is pulled in but can still pull to the bar and never gets solid (the adjustment is all the way in so there is no free play), what I am seeing and hearing is the caliper kind of creak and flex. Note that this is just in the shop, not during movement. I've never had issues with bleeding brakes and I am 90% sure there is no air in the system. I'm about to the point of getting on ebay and getting a Nissin MC. Any suggestions on what to try before I try a Nissin? I'm not sure how I still have hair! Thanks!
  20. Today I'm going to cover how to check and set cam timing, which is something you can do if you have adjustable cam gears in your engine. This is a procedure often performed by race engine builders to ensure the valvetrain performs just as they intend, and ultimately so that they extract the desired performance out of the engine. Adjustable cam gears typically aren't a stock option but are abundantly available in the aftermarket. The following text is exerted from my book, The Four Stroke Dirt Bike Engine Building Handbook, so if you find this info valuable please take a look at the entire book. Degreeing the camshafts is the process of checking, and if necessary altering, the cam timing so that the timing is set perfectly to specified timing values. On stock and performance engines, cam timing can be off slightly due to manufacturing variations in parts such as the camshafts, cam gears, cam chain, cylinder, cylinder head, crankshaft, crankcase, and gaskets. With so many parts having an influence on cam timing, it is necessary to adjust and correct the timing so it coincides precisely with the desired timing values. The biggest factor determining how the camshafts must be timed is whether the cam lobes are symmetrical or asymmetrical. Camshaft lobes that are symmetrical have opening and closing ramps that share the same profile. Asymmetrical cam lobes have opening and closing ramps with different profiles. Symmetric and asymmetric camshafts are timed differently. First we will focus on the timing of symmetrical camshafts. Symmetric camshafts are timed most accurately by determining the position of the camshaft’s lobe center in relation to crankshaft position. A camshaft’s lobe center is where peak lift occurs, which is the most important timing event of the camshaft. Since the tip of the camshaft is rounded, it would be difficult to determine the lobe center by taking a direct measurement of peak valve lift. The opening and closing points of the camshaft are also of little use because the cam opens and closes gradually. This makes it difficult to determine the precise position in which the camshaft opens or closes the valves. The lobe center position is a calculated value based on the position of the camshaft at two specific points of valve lift, typically with valve clearances set to zero. Normally the position of the camshaft is recorded at 0.050” (1.27mm) of lift as the valve opens and 0.050” (1.27mm) of lift when the valve closes. By recording the position of the camshaft at a specific valve lifts, the cam lobe is on a predictable portion of the opening and closing ramps. The center of the cam lobe is exactly in the middle of these two measurements. To calculate the lobe center of a symmetrical cam lobe you will need to do the following: 1. Add the measured opening and closing timings together 2. Add 180 degrees to the sum 3. Divide the answer by 2 4. Subtract the smaller value of the two opening and closing numbers from the answer to reach the lobe center value. Once the actual lobe center value has been determined on the engine, it can be compared to the specified lobe center timing presented by the manufacturer, aftermarket cam supplier, or the engine tuner. If the measured lobe center position coincides with the targeted position, all the work is done. If not, the cam gear will need to be adjusted so the timing is corrected. If you are checking the timing on stock cams and lobe center information isn't presented, you will need to determine the lobe centers the manufacturer recommends. To do this, the opening and closing timing information supplied in the service manual can be used. Aftermarket camshafts should come with a timing card full of useful information to set the cams correctly if they are adjustable, otherwise the lobe centerline can be calculated if the opening and closing timings are known. If you don’t like math, there are plenty of lobe center calculators available on the internet you can use. For the Kawasaki KX250F engine with the stock camshafts, the timing information is as follows: Intake Opens 40° BTDC (Before Top Dead Center) Intake Closes 72° ATDC (After Top Dead Center) Intake Lobe Center = ((40 + 72 + 180) ÷ 2) - 40 = 106° My calculated lobe center timing is 106°. When I check the cam timing, this will be the value the real engine hopefully yields. The lobe center for the exhaust cam can be found the same way. For the KX250F exhaust cam: Exhaust Opens 69° BBDC (Before Bottom Dead Center) Exhaust Closes 49° ATDC (After Top Dead Center) Exhaust Lobe Center = ((69 + 49 + 180) ÷ 2) - 49 = 100° Something not obvious I want to touch on is that if the intake opens after top dead center, a negative value for the opening should be used. If the exhaust closes before top dead center, a negative value should be used here as well. To start the process of checking the timing the valve clearances should be set to zero. Thicker shims can be used and zero clearance can be confirmed with a lash gauge. A degree wheel and pointer will need to be installed on the engine. There are many ways of attaching these items and each engine will provide its own challenges. Here I’ve left the flywheel on and installed a couple washers behind the degree wheel to space the degree wheel from the flywheel. Then the flywheel nut is used to secure the degree wheel. The pointer can be made from welding rod, a coat hanger, or anything else you can find. I’ll be finding TDC with the cylinder head installed, so I used one of the exterior head bolts to secure the pointer. If you will be finding TDC with the head off, choose another location. Before the cams can be timed, TDC must be found. This can be done with the cylinder head on or off depending on the process you use. The piston dwells a few degrees at TDC so more accuracy than zeroing the degree wheel to the piston’s highest position is necessary. Similar to finding the cam lobe center, TDC can be found by measuring equal distances on the piston’s up and down stroke and then confirming that the degree wheel timing is equal on both sides at the measured distances. Dial indicators or piston stoppers are commonly used to do this. HOT TIP: Piston stoppers can easily be made by removing the center section of a spark plug and then tapping a suitably sized threaded hole in the remaining part of the plug so a bolt and lock nut can be installed. The stopper can then be easily threaded into the spark plug hole. Whichever method of finding TDC you decide to use, start by moving the crankshaft to the approximate TDC position. Then without rotating the crankshaft move the degree wheel so that TDC on the wheel coincides with the pointer. Next, set up your piston stops or measure piston travel on both sides of TDC. In this example I’m using a dial indicator which extends through the spark plug hole down into the cylinder. I’ve decided to take measurements at 0.050” (1.27mm) of piston travel before and after TDC. At each measurement point the number of degrees indicated on the degree wheel before and after TDC should be the same if I have found true TDC. If the degree wheel values don’t read the same before and after TDC determine which way the wheel must be rotated so that the values become equal. Then carefully rotate the degree wheel without rotating the crankshaft to alter the degree wheel’s position. Once altered, recheck and confirm that true TDC has been found. This can be a tedious process but is extremely important for checking cam timing accurately. Repeat the procedure for checking TDC 3 - 5 times to ensure repeatability and accuracy. After true TDC has been found, be extremely careful not to inadvertently move the degree wheel or pointer. Do not rotate the crankshaft using the nut securing the degree wheel to the crankshaft. Instead, use the primary drive gear nut or bolt to rotate the engine over. Next, set up a dial indicator on the intake or exhaust lifter bucket, depending on which camshaft you are checking. You’ll have to use some ingenuity here in determining the best way to secure the dial indicator to the engine. I’ve used a flat piece of steel and secured it to the cam cap using the cylinder head cover holes. Make sure the indicator travels as parallel to the path of valve travel as possible for accurate readings. Also makes sure at least 0.060” (1.52mm) of travel from the indicator’s resting position is possible so adequate valve lift can be measured. Once the indicator has been set up, the cam timing can be checked. Whenever checking timing only rotate the engine over in the direction of engine rotation. Reversing engine rotation will result in inaccurate measurements due to the reversal of gear meshes and chain slack. If you miss a measurement point, rotate the engine over until you get back to the previous position. Slowly rotate the engine over until 0.050” (1.27mm) of valve lift has occurred. Then record the position of the degree wheel. Next, rotate the engine until the cam begins to close the valve. Once only 0.050” of indicated valve lift remains record the position of the degree wheel. Repeat this process of checking opening and closing positions 3 - 5 times to check for repeatability before calculating the cam lobe center. Once you are confident in your measurements proceed to calculate the cam lobe center. On the KX250F engine my intake lobe center is as follows: Measured Intake Open (0.050” Lift) 39 ° BTDC Measured Intake Closure (0.050” Lift) 74 ° ABDC Intake Lobe Center = (( 39 + 74 + 180 ) ÷ 2 ) - 39 = 107.5° On my stock KX250F engine the actual lobe center is 107.5°. At this point if I had adjustable cam gears, I could rotate the gear slightly so that the lobe center corresponded to the specified lobe center value. The same procedure is followed for checking and adjusting the exhaust cam timing. Remember if mistakes are made when setting cam timing big problems can result, so it is best to be very patient and focused when performing this task. Always check your work 3 - 5 times to make sure the timing is repeatable and making sense. When tightening adjustable cam sprockets, use a locking agent and be sure to torque the bolts to their specified values. When working with single camshafts that have both the intake and exhaust lobes ground on them, focus your efforts on achieving correct intake timing. Correctly setting intake timing is more important since it has a larger effect on power. The intake valves also have higher lift than the exhaust valves, potentially creating clearance troubles between the piston and valve if the intake valves are mistimed. With your new fangled ability to adjust cam timing, you may be wondering what happens if you advance or retard the intake and exhaust cams from their standard positions? The lobe separation angle refers to the number of degrees which separate the lobe center of the intake lobe from the lobe center of the exhaust camshaft. The lobe separation angle can be calculated using the following formula: LSA = (Intake Centerline + Exhaust Centerline) ÷ 2 As a rule of thumb, reducing the lobe separation angle by advancing the intake and retarding the exhaust camshaft will increase valve overlap, move power further up the power curve, increase cylinder pressure, increase the chance of detonation, and reduce the piston to valve clearances. On the contrary, increasing the lobe separation angle by retarding the intake cam and advancing the exhaust cam will have somewhat of the opposite effect. There will be less valve overlap, power will move to a lower RPM, chances of detonation will be reduced, and the valve to piston clearances will increase. The likelihood of finding more or better power by advancing or retarding the camshafts is not all that likely because manufacturers, tuners, and aftermarket companies already test specific combinations of cam timings to death. In addition, if the lobe separation angle is reduced, the piston to valve clearances should be checked to ensure they are adequate. My advice is to run the prescribed cam timings to reduce the chance of problems occurring. Asymmetric camshaft timing can be set in a similar fashion to symmetric camshafts, however instead of focusing on the lobe center position, the specific opening and closing points will need to be measured. Timing cards supplied with asymmetric cams should have specific instructions for setting timing, but normally valve clearance is set to zero and cam positions are recorded at specific lift heights. Based on the measured opening and closing positions, adjustments are made to the timing until the timing matches the specified values. I hope you enjoyed this exert on checking and adjusting cam timing. As always feedback is appreciated so please leave comments below. If you're interested in more engine building info check out my book The Four Stroke Dirt Bike Engine Building Handbook. Right now we are having a 4th of July Sale where everything on our site is 20% off with the discount code fourthofjuly2017. Just be sure to enter the code upon checkout so you receive your 20% off! So if you've had your eye on our Four Stroke Dirt Bike Engine Building Handbook or even our Value Pack, but haven't pulled the trigger yet - go for it! Availabe at: DIYMotoFix.com - Paul
  21. out of 2t and 4t, what are the best low/cheap maintenance high performance mx bikes?
  22. Does anyone else get a feeling after you work on your bike/quad/truck/car that you forgot something or did something wrong? And you look over the damned thing for like 2 hours afterwards to see what you messed up/what's wrong with it, when almost 99% of the time, everything is fine. I do this a lot and was wondering if anyone else does too. It might just be because I don't trust my own work lol, but I expect my friends to trust my work when I work on their bikes
  23. hey so I have 2010 Yz250f and was riding in the bush and I was getting a clunking sound when I gave it throttle. thought it was the loose chain since it was very loose. later in the ride it starts puffing white smoke straight out of the bottom as well as leaking oil out the bottom. I know something must have broke in the bottom end it was running until I shut it down when I seen that. anybody know what I did?
  24. So recently had the chain ball up and bend my shift shaft on my WR, and figured it was time for maintenance. Compression was on the low side (well...the really low side), so start disassembly to build a list of parts to replace that's going to need replacing and aim going to pick up an Athena 290cc kit to slap it back together. Looks like the engine eat a timing chain at some point and beat up one of the chain guides, easy enough to replace. However it also looks like it may have allowed some debris into the oil system that collected in a cam cap (easy fix with a scotch brite) and far more worrisome into the wrist pin. See images below: Question becomes how worried should I be about the small end of the rod? Is this normal wear for 4t? I'm surprised to see they are like 2t units with needle bearings. Next question pertains Valves (Can of worms I'm sure). Should I stick with the Ti valves. I'm currently looking at the Kibblewhite units as they are about $50 cheaper than the OE Yamaha units. Or should I go ahead and switch the Stainless Steel units? Intake valves look okay, but the exhaust appear to be pretty much shot.
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