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In that you've adjusted the lever, don't forget tht there has to be a little slack where the adjustment screw on the lever meets the plunger that goes through the M/C boot. It's a common mistake for new riders to make to assume screwing the adjustment screw in more gives more travel to the servo cylinder at the clutch, it actually gives less. Jon

Most of us have had good luck with ATF (Dexron to 2006, Type-F 06' on up), it has all the requirements for a wet clutch/transmission environment and is inexpensive so can be changed often at little cost. The Pro clutch has, in effect, a centrifigal oil filter in the form of the Belville spring that collects swarf. Once in a while it's a good idea to take the spring off and clean in that area. Jon

This usually results in more clutch drag as it reduces the overall travel of the servo cylinder. As it's a 96', you might want to pull the clutch and check for fiber separation on the fiber plates. Jon

A full-synthetic (not a a "semi-synthetic" or "blend") seems to work best, like Castrol TTS. The low RPM, on-off throttle places a preminum on a clean burning premix oil. Use a light oil in the transmission, say a 5 or 7.5 weight (74W trans oil is roughly equivilent to a 10 weight motor oil. It's common to use Dexron ATF in the GG's up to 2006, where the Type-F ATF works well in the 06' on up. The ATFs are about equal to a 7.5 weight motor oil. Change it often. If you bike has more than a little drag, it's probably not the oil but a mechanical adjustment problem. Jon

Wayne, I'd do it. Each bike is a little different and the settings will vary now and then. The needle drop was to compensate for the 33 to 38 pilot, as changes to a pilot are a little more dramatic than the same number of steps in a main. Sounds like you are on the right track. Jon

http://www.trialspartsusa.com/tech.html has some good info and spec.'s on the Motoplat ignition. Look under "electrical". Jon

Kevin Schwantz and Roger DeCoster both started in Trials. Jon

Yep. Those of us who have roadraced two-strokes have a permanently crimped left index finger due to covering the clutch lever so we can grab it instantly at the first signs of a power surge as we know the next step is engine lock-up and the dreaded "flying W" into the hay bales..... What happens is that a disruption in the fuel delivery (blockage, venting issue or low fuel) will lean the air/fuel ratio at full romp, giving higher combustion chamber temps and elevated piston pressure (power surge), however, the spike in c/c temp will also then lead quickly to detonation and seizure and then the Flying W.... Jon

Jan, An air gun is good for taking off the bolt but you'll have no idea what the torque setting is if used to install the bolt. I could probably get away with it because I have a feel for how the air gun works/feels and about 50 years experience, but even then, I like to use a good torque wrench.. Jon

The flywheel bolt is a standard right-hand thread. You can hold the flywheel by using some plastic or cotton rope, about 3/8th in. Take the plug out and poke a little of the rope through the hole while turning the flywheel to feel when the piston is coming up to TDC. Before TDC back the flywheel off a little and push some rope through the hole to fill the chamber, then turn the flywheel to lock it up. If you locked the flywheel on the wrong side of TDC, be sure to remove all the rope before doing the process again so as to not get it caught in a port. Drop the needle one groove means to place the circlip on the top of the carb needle one groove higher, which will have the needle lower at the static setting. (it "leans out" how the needle operates in the slide opening range). Jon Forgot to add: when installing the bolt, go to about 54 Nm and re-check after a couple of heat cycles (rides).

Wayne, If the timing, due to key shear, has retarded/advanced slightly, this could lead to possible overheating and poor running. It could also be stale fuel or water in the fuel. I'd go with a #38 pilot jet and drop the needle one groove (raise the clip one groove). The other jets seem to be in the ballpark and the #300 float needle flows more than enough fuel to prevent high-speed starving. Check the float level by tilting the carb body so the float arm tab just lightly touches the spring loaded pin on the float needle. If the arms are then parallel with the gasket surface of the body that the bowl contacts, you're fine. While you have the carb off, I'd take the manifold off, check the reeds (hard to know what else the previous owner took off) and then use a little sealer on the gaskets when re-assembling it. It's probably a standard steel/rubber reedcage/manifold assembly, so don't overtighten the four screws holding it in (that will "bow" the manifold between the screw holes and allow air in). This will eliminate a manifold air leak as a cause. Jon ps. Fear not. Everything can be fixed.....

Hi! I have two 85' TY350's (owned one since new) and have a fair amount of experience with them. I also live just north of you in northeastern Oklahoma, so we're neighbors in a way. I use a 50:1 premix of a full-synthetic, Castrol TTS with very good results. Jon

I'm assuming the "33" is the pilot and this is a standard Keihin PWK28 on a 300 Raga (usually mid-40's works well). That seems way lean for a pilot on this configuration. That would be way lean for a Dellorto in fact (usually #36-38) and may be the cause of the chop/pink problem. Air screw adjustment should be done according to ambient conditions (blip throttle and in/out to get best reponse). The backfiring problem is somewhat of a puzzle and could be flywheel alignment related, as well as an air leak (usually manifold). The shock loads on the flywheel/crank taper for a Trials bike are huge in comparison to most bikes and the flywheel bolt needs to be checked now and then. Jon

Jan's link will help a lot. Your friend may also want to make new preload spacers about 8 or 10mm longer (the grey PVC spacers above the spring) and use about 320cc's of Dexron ATF (about 7.5 weight) as fork oil. At 280 lbs, he should look into using heavier springs as you can only compensate so much for the added sprung weight. Jon

Hmmmm, scorched plates. Did you check to be sure there is a little clearance where the screw on the lever meets the plunger that goes into the master cylinder boot? If adjusted in too far the result would be: clutch slippage (scorched plates) and reduced servo cylinder travel (clutch drag). Jon

What oil are you running in the transmission? Jon

Yahoo! My copies arrived today. Great work! Jon ps. That's a catchy little tune with black screen after the credits.......

Wayne, If the problem persists, you may want to go up a step or two on the pilot as the pinking occurs upon shut-off, rather than mid-range or open throttle. Jon

I would think (and based on my experience) that a well-maintained and properly jetted 2T does not need to be cleaned out at every startup. I'm also quite surprized that the EVO runs a non-projected tip plug, two steps colder than the normal heat range in a liquid-cooled Trials bike. They must have made some radical changes to the combustion chamber. Jon

When you ask a bunch of riders what is the "best" of anything, you'll get a bunch of answers. Here's my opinion of the best based on my experience: NGK BPR5EIX-11 set to .6mm gap. The "P" dictates a projected tip (helps the combustion process) and the "-11" means it's an "extended gap" plug designed to fire at .044" (1.12mm). The Iridium plugs take less voltage to fire and have an extended heat range as well as not being prone to fuel-fouling at low RPMs. 80/1 premix ratio of a full-synthetic oil, like Castrol TTS for instance. The full-synthetic oils tend to run cleaner at the on/off throttle, low RPMs encountered in a Trials engine For the 2008, Type-F ATF, change it often No workshop manual available, just parts and owner's manuals Jon

Make sure that the rod that goes from the lever up into the M/C has a little slack (the piston in the M/C has to drop down completely to the stop at the circlip, same as the front brake/clutch M/C's). Sometimes taking the rod out and using a Phillips screwdriver to push up on the piston will give a lot more travel and make bleeding a lot easier. Jon

There are three lengths of valve cores, all should work. Jon

If the clutch is designed for mineral oil use, the top cap on the M/C will be a green color (black color for DOT-3/4/5.1). DOT 5 is not compatable with DOT-3/4/5.1 fluid and is Silicone based. Jon

Charlie, As I understand, the process changes the temper of the disk and/or possibly the pads depending on their composition. When I had a bike with the single AJPs, I had pretty good luck with the EBC Kevlar pads. Jon

You may want to check the tire for small leaks. We normally run about 4 psi in the rear tires when riding (and about 6 psi in the front). They are tubeless so a small leak can be fixed with a tubeless tire repair kit and you won't have to take the tire off to do it. Jon