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About matt4x4

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  1. matt4x4

    What year steel frame

    2005 was the last year they made the steel frame, that is also the most advanced one of the bunch, not that there are many differences between the years, but there were always slight changes. The frame itself did not change over the years.
  2. Definitely Jetting related, start by getting your pilot dialed in according to directions in manual once the bike is at operating temperature (40 does sound like a good place to start but you may find you need to be a bit richer). Big bore kits often require a needle change too in order to get them smoother in the mid range, lastly, wide open...see if it pulls stong and even or falls on it's face and adjust accordingly.
  3. matt4x4

    2010 YZ250F - Pops On Deceleration

    Hey William, I know you know a lot so I'm not trying to challenge you here, but saying fuel screw is for idle only is misleading, the pilot ciruit is ALWAYS in play, it does not magically shut off, however, it combines with the main jet and needle profile to provide you an overall metered amount of fuel through your full throttle range. If a bike fuel/air mixture is perfect everywhere except it's lean on the pilot, you would change out the pilot to a richer one but then put a slightly leaner main into the bike - this adjusts your pilot only, the resulting combined fuel/air deliveryfor the rest of the throttle range will now stay the same as it was before the changes because a richer pilot+leaner main = same as prior to changes during throttle range with richer idle to 1/4. Neddle profiles come into play here too but that's probably too much for most to digest. On a basic level: pilot=idle pilot+needle profile+main=mid ranges pilot+main=full throttle popping is fine but if it's excessive, it's ok to richen your pilot a bit to reduce it some because most likely it has to do with the cooler temps causing denser air - excessive popping means you're too lean, right now up here, we have 32 degrees in the morning and need to richen our bikes by about 1/8 to 1/4 turn richer on the fuel screw, this is fine and the bike will still start fine when hot, because the bike will needs to be richer throughout the full range because the cold dense morning air makes the mixture leaner through your entire throttle range, by 11am temps are up to the 60's and higher and we have to lean the fuel screw back to where it was prior to adjusting it in the morning because the air is less dense now so we require less fuel to get the same ratio.
  4. matt4x4

    Did I just nuke my valves?

    Rookie mistakes, at worst you stretched your cam chain, it takes more than that to screw up your cams or crank, I would play it safe, remove the cam chain, inspect it, if there are no marks on it from scraping hard against the tensioner and it was a brand new chain, it should be fine, if it's still the old chain, it should be replaced anyways so chuck it and spend 13 bucks - longest I'd run a chain is 40 to 50 hours at which point you need to rering your piston or replace your piston anyways (two things to do together). I just posted the whole cam installing procedure in another cam thread in this forum so look that one up for the proper procedures on everything. Oh, as for nuking your valves, if you turned it by hand without using a ton of force or a persuader on your ratchet, you will be fine. gotta take a pretty hard hit before you'll bend a valve.
  5. matt4x4

    07 YZ250f valve adjustment issues

    When buying a used bike, check valve clearance right away, check shim sizes right away, push down on each valve and look at the seating surface on the valve and also inspect each valve for signs of damage, a chipped valve is never good no matter how small the chip is. Shim size and valve surface condition will give you a good indication of where your valve and seat is at in it's lifespan. Overly thin shims but a decent valve surface tells you that your seats will likely need replacing the next time you do valves, you can only cut valve seats so many times, after that you run out of shimming options. Always put the individual shims AND buckets back on the same valve, sometimes people screw up the order of the buckets especially and then wonder why the cam no longer spins as freely, they used bucket i1 or valve i3 etc. and it screwed up the clearances because not all buckets are machined or wear equal. Shims should almost click in place, make sure they are flat. Lube everything before assembly. Valve seats need to be cut with a proper machine like a SIDI, it is an extremely precise procedure which you cannot do by hand, plus, it only takes off a small amount of material, you could never do it accurately by hand and your seats would be rendered useless. Valve stems rarely stretch - that's a misconception, the surface of the valve wears and allows the valve to move further up towards the cam profile before it seats, this in turn takes up some the free play we call valve clearance. Easiest way to get your cams in is to install one cam with the chain over it, then pull the back of installed cam up some (this drops the cam gear some on the front side, allowing more play in the chain), take your second cam and roll it under the chain and into place from middle of head towards outside with a bit of an angle on the cam, it should roll into place with little to no resistance. Hard to explain but once you do it, you'll see what I mean about getting more free play under the chain and rolling it in. If you are off a bit on the dot alignment, unroll it a bit until you have some play on the chain, lift chain off gear and spin gear in the direction you need to move it however many teeth needed to get the dot lined up. Use a little oil on everything when you assemble so nothing is dry for startup. Get your cams lined up properly front to back, place your half ring and cap on, tap cap down gently using butt end of screwdriver, torque it down to 3 inch lbs less that spec in 1/3 increments in a criss cross pattern. Install your tensioner and set it, then turn your engine over using a wrench only for a few cycles, set it to TDC again and look where everything lines up.
  6. matt4x4

    XR50 Getting flats every time we ride

    clutch should be the least of your worries, Shorty is right about kids picking that up fast. The KX65 is a very relaible bike, just re-ring every 30-40 hours and replace piston every 60-80max, everything else generally lasts a long time with poper maintenance.
  7. matt4x4

    Clicking in the rear

    Set the bike on the stand both wheels off the ground, lift your rear wheel, if you hear a click then, it's most likely your lower shock bearing (it gets a lot more crap flung at it than the upper and wears out much faster if you do not service it regularly) You generally do not get clicking sounds from the linkage bearings, they just tend to seize up and rotate the shaft instead...unless of course they have been in bad shape for a very long time. Just take it all apart and service what is serviceable, Replace what is junk, it's not that much work. Most bearings can be obtained at a bearing supplier for WAY less than OEM or aftermarket, you just need the outer diameter, Bore (innder Diameter) and depth of each bearing. If the shafts are rotted to crap and the seals are beat too, you're best off just getting a full kit. Some shafts can be brought back if not too badly rusted and you can also get seals at the bearing supplier's with the same set of dimensions for each seal.
  8. matt4x4

    My sons first ride

    Sweet! So the first thing you want to do is get him comfortable with the brakes, do this in an open space, place a cone 40 feet down the field and tell him to ride up to it smooth and stop with his wheel even to the cone. Teach him the difference between front and back brake and things that can happen when using either. Once he becomes comfortable, teack him skidding with the rear barke and how to keep it upright in a skid. After the brakes are mastered, put two cones about 30 feet apart and have him do figure 8's around them, this teaches him cornering in BOTH directions evenly and that is very important since everyone is better at turning one way or the other, this will make him good turning both ways. Oh this brings back memories, unfortunately, my little guy is now 12 and has ridden for more than half his life and now schools me and many others every time we go to the track.
  9. matt4x4

    critical torque?

    I ALWAYS stay 10% under specified torque for cam caps and NEVER had an issue yet, no score makrs on them or anything....torque your caps in criss cross pattern in 1/3 increments, I also like to make sure everything is seated properly by using a rubber mallet to tap them on and tap them again after the first round of tightening. Staying under the max torque, makes it less likely to overtighten the caps if your wrench isn't dead on, overtightening the caps just a bit can lead to major cam problems, your cams should move freely side to side by just using 1 finger on them. The harbour freight torque wrench will do you fine as long as you take care of it and ONLY use it for what it is designed to do, just remember to ALWAYS take the load off the setting mecahnism when done and store it properly in the provided case.
  10. matt4x4

    Front fork maintenance.

    You are ok, 03's still have the old style single chamber forks, you would know by the 2 part fork caps that require special tools.
  11. just don't torque them to the full torque value, going 2/3rd is plenty to get your clearance measured (torque down in star pattern), when you do final torque, stay about 5 in/lbs below the spec because that's tight enough and you NEVER want to overtorque those caps.
  12. matt4x4

    Engine Rebuild Questions

    Honda East Toledo, I definitely second that!!!! Yes - many bearings can easily be obtained through your local bearing house, bore diameter, outer diameter and depth are all you need, if you need one with a seal on one side only, buy a sealed bearing and remove the seal with a pin on one side, the crank bearings need to be OEM since you cannot get them with the groove milled into them from a bearing house, if you are good with a dremel, you CAN grind recesses for the retaining clips into bearing house bearings but flush them well after. Case seals are the same as bearings, provide them the dimensions and they can likely get the seals. Unless your case dowels are messed up you do not need to replace them, honestly, the crush washers for the oil lines also do not need replacing, I've never had one leak yet when reusing them. Check the internals of your oil pump, if the cam mechanism and parts are badly scored, replace them too. Carefully check your shift forks for rub marks and all gears for chips or damage, also check the dogs where the gears mate, any sign of wear on the dog edge or mating face and you should replace the gears. replace all lock washers in the motor unless they still have a fresh locking tab left on them, never reuse a locking tab. You will definitely want to replace your output shaft oring, collar and seal, this can be done after it's all together but you may as well order the parts right away. I also second the timing chain, and replace that every 40-50 hours during ownership, at which time you should also do rings or rings and piston every 100. Putting it back together...assemeble everything in the left case, make sure you can work the tranny through all 5 gears, it will be rough and hard to do without the right case installed but with enough wiggling it should shift through, apparently there's nothing quite as frustrating as putting the cases together and finding out it only shifts thu 3 gears lol. Remember that temperature is your friend, I have a shop stove, heat the cases to 200f and freese all bearings being installed, gently tap them in touching the outer race ONLY. Once the bearings are in, heat left case, freeze crank and drop it in. Once you are ready to assemble cases, heat right case while adding permatex motoseal to left case mating surface, let it set about 2 minutes, drop right case on and tap into place using rubber mallet. Insert your bolts, lightly snug all and then torque down to spec working in 1/3 torque value increments in a star pattern like you would do a wheel. Check everything twice as you work through the reassembly, better than leaving something out.
  13. matt4x4

    XR50 Getting flats every time we ride

    you fix that problem with a kx65, if you don't know what that is, it's a green part you buy and put under your kid's butt to help him become an accompished rider Sounds like your boy is moving to the real bikes, I remeber when my boy was 7, in that summer he went from a crf50 to a 70 to a kx65. first ride on the kx and he never wanted to ride a crf again. He's 12 now, and an accomplished little racer, racing 3 classes this summer, going to be a busy little man.
  14. matt4x4

    Front fork maintenance.

    Depending on the year of your bike and the forks on it, remember that Dual chamber forks require just over a liter of fluid (about 1.3L total) which is more than single chamber forks need, using 3/5/10/15 wt makes little difference to the feel of the shocks, the valving is more what decides your feel. Most people use 5, some of my friends use 10 or 15.
  15. matt4x4

    My seat is too hard!

    wear padded bicycle shorts under your riding pants, they REALLY help and get several of these (they even make it for the ladies now):