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If they don't have it, you can make one. Use a short length of rod/tubing and weld/braze a 16mm or 11/16th" nut to the end (a slight angle to the nut makes it a little easier to use). Cheers. Jon

Tom, I think the GasGas forks are 10mm and the Marzocchi forks are 16mm Allen hex size. Cheers. Jon

Oh, I get it, Mark....One of the things I miss out here in the Midwest is that the alternative papers don't carry "Zippy" cartoons like they did in California, part of the culture shock I endured as a result of the move........ I haven't tried the 3M adhesive (what we used to call "Gorilla Snot" and we used to use it like duct tape to stick and seal things on our bikes) yet on the soft grips, it smells a lot like the Renthal stuff though. Jon

Thanks! That's the first time anybody has accused me of having style......... Jon

I used to do that also but I've found that some of the new grips, like the Renthal super soft, are real sensitive to solvents, even those in most grip glues and can split. I tried to use my regular Honda grip glue on a set of Renthals and they promply came apart (split) and Scotts seem to soften them when I tried some on old grips, so I only use Renthal grip glue. The medium and hard grips don't seem to be as solvent-sensitive. The Renthal grip glue is a bear to use as the stuff sets quite fast and you usually only get the grip on half-way, especially the thin throttle side. A trick is to spread the glue on and use a little around inside the first part of the grip and then spray a little alcohol on the bar and inside the grip and it will slide on easily and after the alcohol evaporates, the grip will be solid. Jon

Yep, I'm Stoodley, but only believe half the crap you've heard about me, oh, and the other half is probably true too.... Jon

Sometimes they can be a little stubborn. In suspension work, a propane torch is real handy to heat the top part of the lower leg to break the bond the seal has developed (it also works on o-rings). The outside of the seal is designed to form a bond with the bore of the lower leg (like most seals) and a little heat really helps. I use the torch a LOT when doing suspension work. I know it seems like you're going to "break" something when snapping them apart, but that's the best way, just try to pull straight opposite from each other. I'm assuming you have taken the cartridge out by spinning off the "basebolt" at the very bottom of the lower leg? Jon ps. The guy in the video has made sure the seal is lubed and the legs pop apart easily before the camera rolls, nobody wants to look like a dufus on video (well, most of us....).

oGenerally, it will vary slightly according to jetting (pilot/slide cutaway) and ambient weather conditions, so the best setting is what ever that particular engine needs. Start about 2 turns out to start (initial setting is somewhat irrelevant) and (warmed up engine) blip the throttle from idle and turn the screw in/out to get the best response, then you're set. Cheers Jon

I think that number is M01411100. You don't always need to replace the grudgeon pin, but it's a good idea. It's probably had 7 years of use and it is an inside bearing surface. It will extend the life of the bearing if replaced. Jon

There's a good chance you may not need to change them. Prop the bike up on the sump guard and take off the upper triple clamp and unscrew the retainer on top of the steering stem. Drop the stem down a little so you can clean and inspect the lower bearing (don't forget the outer race up in the headstock). If the bearing rollers/outer race are smooth and not pitted and the bearing is not rusted and in good shape pack the rollers with some good waterproof grease and smear a little up on the outer race. Don't forget to inspect the o-rings that seal the headstock, top and bottom. The lower bearing takes most of the load so take your time inspecting that one. Setting steering stem bearing preload is like truing rims, go slow, take your time and expect to adjust 3 or 4 times until it's right. Leave the upper triple clamp bolts loose so the upper clamp can move up or down minutely when changing the preload setting. Start by spinning on the adjuster ring till it lightly bottoms and them back it off a little and install the clamp and top fastener to maybe 20-24 ft lbs or 27-32 Nm and the rotate the forks to see if they drag too much (you'll want a very slight drag) at which time you'll want to back off the adjuster ring a little and try again. If they are free, grab the front forks and push/pull to see if there is any play and adjust accordingly untill you get the right combination. Don't forget to tighten the upper clamp capscrew bolts. If the bearings are trashed, let us know. I have a special puller I made to get that lower bearing off the steering stem and I bet riders have a few tricks they've developed to get that bearing off. Jon

Probably the best advice I can give you about transmission work is you can never be too careful. Keep both gearsets complete until you are ready to work on them (and only work on one at a time) and arrange the parts lengthwise on a clean shop towel in EXACTLY the way they came off the shafts, especially the spacers/washers/circlips. Another common mistake I see is that a mechanic will find a knackered roller bearing in a transmission and think that just replacing that bearing will make things whole again. The Pro transmission has, for instance, two split-caged roller bearings, but they are actually only 1/3rd of the "bearing", as the shaft is the inside race of that bearing and the inside of the gear cluster is the outside race. If you just replace the roller cages and the gear/shaft surfaces are compromised in any way (they almost always will be), that bearing will soon fail and you'll be right back where you started. If a roller bearing is munched, you will usually be better off in the long run to replace the whole "unit" of bearing surfaces. Jon

Zippy, I think you mean what is also called "Mechanic's Tape", which is the black cloth (not plastic), double-sided (sticky on both sides) tape which we used to use for tape-type repairs before plastic electrical tape (sticky on one side) was common? We used it on the flat track grips as you really didn't a grip to come off when you're sideways at 100 mph... Another tape I use now (I gave up on regular plastic electrical tape on bikes) is what's called linerless splicing tape, which is a rubber based electrical tape and is real stretchy and bonds to itself and is waterproof. It doesn't unravel like the plastic stuff does (when wrapped tight on itself it's like it becomes one-piece and you have to cut it off rather than try to unravel it) and I used some yesterday to do a temp fix on a carb manifold so a rider could finish the Trial. It costs more than the common plastic electrical tape but I've found the benefits far outweigh the extra cost. Jon

Back to your problem. If the squish measures out within reason (and the correct piston was installed), the next place I would look (provided your jetting is o.k.) is the manifold/reedcage area. Sometimes the older bikes develop cracks on the manifold and any air being sucked in there will lean out your jetting. Another problem I see there, is that the manifold will be tightened down too much and that will "bow" the sealing area between the screws and allow air to be sucked in there. By the way, what is your jetting? I'm sure that the TY250 guys on the forum can tell you if there's a problem there. Cheers. Jon

Now, THAT looks like a fun bunch to hang around with! Jon

Chris and I are close friends and we had a good time working together with Bruce for his TY portion of that website. When Chris and I get together we usually drive others to drink with our needlehead ramblings about engines, suspension and such.... Jon

I would not think painting them completely is a good idea as, or so you've already found, the paint flakes off due to the underlying steel flexing and the outer part of the coil rubbing against the upper tube and ends up in the shim stack, messing up the damping. Sometimes there will be paint stripes on the springs to indicate their spring rate, but other than Eibach springs that have a special flexible coating that works well, most springs are bare. The stock springs generally work well for most riders as they can be preloaded (+ or -), as necessary, to suit and you can adjust for bottoming problems by an oil level change and change damping characteristics (individually for compression and rebound, which is why they don't have both in the same tube like MX bikes) by using different oil viscosities. You may want to have the springs glass bead blasted, which will remove the paint but not disturb the surface area. Jon

I agree with you. Unlike the 350's we got over here (whose squish bands measured from .078" to .091" on average and rattling was the norm) the 250's seemed to run fine, not detonate, and I think the performance, overall, was better. The reason I thought he should first check the squish on his personal engine were the two statements: "engine is fresh" and "pinging it's head off", which makes me suspicious of what should be verified first as I've seen some very "creative" ways to choose and assemble parts. When that variable is dispensed with, then he needs to look at a leak-down test (or a least a soapy solution on suspect areas, especially the manifold) and exhaust system examination to begin with. I'm with you, he shouldn't need to remove any material and from my experience, the 250 (well set up and maintained) is not prone to pinging. Jon

Hi, I've got an 85' TY350 I've had since new and have encountered a little of what you speak of. I'm not sure if all my observations will be spot-on as mine is a 350 and yours is a 250, but you can consider that. I'll try to speak from direct experience, rather than theory or belief, and that will probably help me stay out of trouble (does not always work for me, however...). From what you describe, you probably want to find out what the measurement and configuration of your squishband is to start with. You can do that by taking the plug out and form two short strands (maybe 5" or so) of soft solder into curves and using a wrench on the flywheel nut (don't use the kickstart) turn the engine over so that the piston is close to the top (TDC) and insert the solder, one to the front and one towards the back and then turn the piston past TDC and remove the solder. The reason to use two pieces of solder is that compensates for "piston rock" and give a more accurate result. By measuring the thickness of the squished ends of the solder with calipers, you will know what the clearance is between the piston and head at TDC. Another thing it can tell you is if there is a problem with the configuration, meaning that the squishband and piston crown are not "paralel" or have the same clearance over the area where they meet. Generally, a clearance of about 1mm (.039") is close to optimal in a 250/350 Trials engine and my 350 measured out at .087", which needed to be dealt with by some machine work which has eliminated the knock ("ping") altogether. I'm not sure what the configuration of the 250 combustion chamber is but the 350 had the trapeziodal type (rather than the later, and better "hemi" type) and that type lended itself to pinging problems when the squish was off. Not all the TY's rattled, but it was fairly common in the 350s imported to the U.S. 95 octane and 50:1 should work fine from my experience and I use Castrol TTS at 50:1 in my TY with no problems. Since you ride on the street you may need to re-evaluate your jetting, possibly, as you want to avoid detonation at all costs. Detonation is caused by the unburned air/fuel mix around the outer edges of the squish area reacting to heat and pressure by auto-igniting, essentially creating another flame front moving to the center of the chamber where it meets the "other" flame front caused by spark ignition. When those two fronts collide, the pressure in the combustion chamber spikes, usually before TDC, and the resultant loud "knock" is what you hear and it's the functional equilivant of smashing the piston crown with a sledgehammer. It's easy to tell when an engine has experienced detonation as the outer piston crown and outer edge of the squishband in the head will look like it's been sandblasted with large grit. Why don't you measure your clearance and let us know what you find? Cheers. Jon

Alan's idea usually will fix the squeal and the "brake quiet" stuff usually looks like hi-temp Silicone in a tube. It effectively bonds the pads to the brake pucks and dampens the vibration. The "squeal" is the high-frequency vibration of the pads on the disc and it tends to drive me nuts also (which is usually a very short trip).... Some brake pads use an "isolater", composed of a hi-temp woven fabric and stainless steel pad backing, but this is rare in Trials brakes. Often, cutting a thin "X" on the pad with a hacksaw will help channel grit from the center outwards without diminishing the braking performance and prevent squeal. Sometimes it depends on the pad composition (and the disc alloy), if it is organic or something like sintered copper, but the only non-squeal pads I've found were the Kevlar composite ones and I even managed to get a set of those to squeal one time... Jon

Shaun, I'd first set the lever stop to where it's comfortable for you and then check the plunger rod on the back of the lever to make sure that it has a little "slack" before it starts to press on the piston inside the master cylinder, otherwise adjust it back down till it does. You need the piston to return completely back down to it's stop at the circlip. Each bike is different, so the settings for the 125 may not work on your bike. I doubt you need a new M/C, but you may need a rebuild kit if the seal has worn to the point where it is inconsistant in operation. Sometimes a worn seal will not "seal" until it is part way down the bore as the first third of the bore gets the most use and only a few thousands of taper in the bore will cause problems. I'd check the lever adjustment first and then maybe opt for a rebuild kit. I'd also try to keep the line ziptyed up when taking off the M/C (or try to replace parts with the M/C held up) so it doesn't drain down and you'll find bleeding the rear brake a lot easier. You can often bleed off any air from the system by pressing on the M/C piston with a Phillips screwdriver after assembly. Jon

You have the "regular" TXT model, also known as the "Edition" model in later years, as the Pro was not released until 2002. Jon

Kev, The "TXT" is essentially the older model engine and frame and the "TXT Pro" is the newer, lightweight engine. It's kinda confusing as they call both TXT's, but actually, when the Pro first came out, it was designated as the "TXXI" model (I have an 02' Pro-first year- and the "TXXI" decals are on the radiator guard), but apparently they didn't follow through with that, hense the confusion. Jon