jse

Interesting concept, but I doubt it is anchored in mechanical reality. Starting proceedure is essentially the same as for any 2S bike: push slowly on lever to put piston on compression stroke and then engage rachet mechanism at top of lever stroke and use body weight to fire it off. That way you don't have to use leg muscle (and energy), kicking back, and use weight instead. Jon

Wow. I am now totally confused, yet I feel strangely enlightened. I agree, time for another beer...... Jon

I think you've got the Dellorto VHST26BS carb on your 03' (the only year they used it) so you want to be sure that the "starter jet" is also clear (it feeds the "choke" circuit). When you kick over the bike over, don't open the throttle at all with the "choke" lever up (actually not a true "choke", but an enrichening device). Pilot jets orifices are very small in diameter and it's easy to mistake them being open and clean. I'd put a new plug (BPR5ES or better yet, a BPR5EIX set at .024", .6mm) in, as it's not unusual for a plug to spark when out of the head but fail under the pressure of compression when installed. Check for fuel flow out of the petcock and that the floatbowl is filling (theres a disk filter on the side of the carb). Just to be sure, you might want to make sure the flywheel key is not sheared (the bike may not have been running when stored). That's a start, let us know if the problem persists. Jon

Hmmmmm, what other way is there? This is a very interesting question, but darn difficult to answer objectively as there are so many other variables involved. My subjective experience is that it tends to make tight turns a little easier but it could only be that it's the placebo effect working and I only "feel" that it does. In Trials we seem to have more physical ability to effect steering geometry than, say, roadracing and the surfaces we face with the bikes are much more varied than just about any other sport, so it could be that the slight change in the fork height/tripleclamp area is not primary but results in a secondary effect, like more front weight bias dropping the tubes further into the lower legs and effecting the rake measurement. Copey, I breathlessly await your astute, three-beer final analysis of the question..... jon

Your wait is over......yes. No, maybe, hmmm, let's see, front end weight bias: Wf=Wt(L-x)/L Wf=front-end weight Wt=total weight x=distance from front axle to CG L=wheelbase Well, Copey, I think it does in my experience. Jon

Neat, (I'm also sure I've got a jumper just like that in a drawer somewhere too) I saw my first one here in the U.S. at the Ute Cup in Colorado last month. Very light and responsive and very pretty, inspite of the two days of rain, hail and mud it had to soak up running up and down the mountain. Jon

Actually, I think he got it from Bill Clinton...... Jon

Geeez, this one's at least interesting and a little shadowy in proposal, although it sounds like it was written by C3PO trying to make it sound like a Victorian novel....... Jon

Well, poop. I can't wait to take one apart..... I don't recall if I mentioned an article I did on sidevalves for Trials Comp some time ago (based only on the computer design model and before the videos/photos were released), it's reprinted on the GasGasUSA website: http://www.gasgas.com/trials_home.htm . Jon Went back and saw that I did, disregard this post......

Me too. I'd just dump it as it's not worth your time top respond. Besides, ANY e-mail that begins with "ESQ." and "My worthy fellow," causes my finger to automatically hit the "delete" key......quickly. Jon

Me too. The fluid property breakdown is not the problem as much as contaminants such as water and fine grit. With no filters, no external cooling and an open breather, the transmission case in a Trials bike is prone to ingesting and retaining a fair amount of gunk, especially in the case of a wet Trial. One of the reasons why, if you want to avoid future problems, you NEVER want to store a Trials bike after a wet Trial without first changing the trans fluid. Jon

The stem will need to be pressed, carefully and accurately to make sure the lower flange of the stem seats fully in the recess of the lower clamps. Generally, stem breakage is more likely to happen if the stem bearings and/or fork clamps are loose as this retains more shock to the stem, rather than transfering it to the frame. Jon

You might try re-packing it a little looser. The internal core of the final muffler is part of the "included length" of the designed exhaust system and you may have reduced the internal volume. MX expansion chambers will be smaller volume for torque values and roadrace chambers will tend to have more volume for higher rev's (that's a gross oversimplification, but may be, in part, what's working here). Did you do anything else to the engine..at all, when you packed the muffler? Jon Oh, and you may want to check the core as it may have shifted during re-packing and mis-alignment will kill rev's quickly.

I'll stick my nose in here since nobody answered you, but I may be missing the point, if you can use 3rd instead of 2nd to climb hills, isn't that better, traction-wise? The loose packing, like SilentSport, should probably be packed looser than you think, as the directions say, and not jammed in, like the density of roll packing. I've had good luck with SilentSport as it is much easier to pack the odd-shaped Trials mufflers and you can add to it in a pinch (like the Trial is the next day and all the shops are closed, but the muffler still needs packing). The sound will be different, and maybe you may be mistaking the performance of the bike based on your previous experience with the old packing? Jon

Probably the main or rod bearing (or both), either way is major work. There are other possibilities that could cause the lockup so you'll want someone experienced to take a look at it. Where are you located? One of us can probably give you the number of a good dealer who can help you out. Jon

First thing I'd check before starting the bike is the throttle cable, sometimes a branch will pull the carb ferrule up out of the adjuster fitting on the top of the carb. Make sure that the cable housing didn't get munched somewhere, which will deform the spiral housing under the black plastic outer covering and sometimes cause the inner cable to stick, and if the inner steel spiral is pulled apart, will extend the length of the outer cable housing and hold the slide up. Dirt in the throat will often cause the slide to seize in the channels it rides up and down in. I'd pull the airbox and inspect the carb boot and carb bell for dirt/grit, which, and if it is there, means that dirt is passing through the filter or the filter is not fitting on the airbox base correctly and dirt is passing past the sealing part of the filter. A wet Trial will tend to wash fine grit through the filter cells, depending on what brand of air filter oil you use. If the slide sticks open and the engine starts to scream, hit the kill switch quick. If it runs that way for any length of time, combustion chamber temp will cause the fuel to auto-ignite and the kill switch won't work, which, in case, you'll want to take off a glove (holding it with the other gloved hand) and stop up the exhaust and when the revs drop, the kill switch will usually work. Jon

I've been told by my PetroEngineer buddies that not all ATF is fully-synthetic and it depends on the brand. I've never had a problem with it (ran it in my 96' JTR370 for many years) and in fact, use GM AutoTrak II transfer case fluid in my 280 Pro, which is synthetic. It may have to do with the fluid change periods? Jon

Thanks. This was a really serious problem at the time and several riders had careers ended when they dropped, in effect, three stories and the bike's skidplate landed on the peak of the last jump (known as "casing a jump", the engine cutting out killed the momentum and speed up the onramp and the bike landed short of the downward landing ramp). This meant no suspension to absorb the shock and ankle bones were often shattered by the violent impact (spinal problems occured also). Jon

I agree to avoid the synthetics. It's suspected that some synthetics will form an acid when mixed with water/moisture (impossible to avoid, and the gears will really mix things up) and that particular acid attacks the adhesive that bonds the fiber to the steel plate in some clutch packs. I've never had that problem with my bikes, but I've seen delamination in older clutches (I suspect they have changed the formulation of the adhesive in newer ones. It may be that I am faithful to the 5-10 hours max of use, trans oil changes (or after a wet Trial) so that there is much less moisture build-up in my trans. Jon

Years ago, we ran into a similiar problem with siphon effect in the SuperCross bike's carbs, before the carb manufactuers started double-venting (actually four lines and an overflow line for the bowl) the float chambers (they saw the same problem). When the carbs had single vent tubes on either side of the carb body (like the Trials carbs now) and the lines were run straight down, the vent lines would have fuel in them from the bike being bounced around on the track and when the rider would hit the on-ramp to a big triplejump, gravity would pull the fuel out quickly and create a vacuum in the floatbowl, causing the engine to miss or cut out (NOT a good thing on a steep ramp to clear a big triplejump). We figured out the cause of the very dangerous problem and all the carbs now, like the PWK39, have a "T" at the vent fitting, one line is run down and the other is run up over the carb body. This way the fuel can pull down the lower tube and the upper tube is able to draw air so a vacuum is not created, therefore no more problems. Not sure if this will help, but if siphon effect is the cause, you can get "T"'s at aquarium supply stores. The center barb can be cut back a little so it does not stick out so far and use a short piece of tubing to attach to the vent outlet on the carb body, run the bottom line down and the top line up and over the front of the carb. Jon

Jan has a good point. Sometimes fine grit will prevent the brass plunger from fully seating (and shutting off fuel flow to the "choke" circuit) and the engine will run slightly rich. The best plug I've found for the GasGas is an NGK BPR5EIX set at .024" (.6mm), but it sounds like the problem is not with your plug. Is your bike a TXT or Pro and what jetting are you running? That may be the problem, and if not, it will help narrow down the possible causes. Jon

A friend uses the S3 clamps that also raise the bars up and are more adjustable forward and back to give a little more "room" for tall riders. They also appear to be stronger than the stock "clamshell" clamps, which he broke. Hebo also makes a taller set of "fat" bars and I use a set on my Pro as I found the stock bars bent me over the front a little too much. Jon

I'm not familiar with this problem with other engines and I find it very interesting, especially as to why it is occuring, even considering the possibility that it is related to oxygenating pump fuels. I'm reluctant to offer this suggestion as it only relates to a possible cure for the symptoms, rather than finding the cause of the condition. When we store racing two-stroke jetski engines after a race (and they deal with a LOT of water) we use what's called a "fogging oil" in the intake, specially designed to displace internal moisture in personal watercraft engines or engines put in storage. I've liked the Kawasaki brand and it's easily obtained in shops. It's sprayed into the intake with the engines running to coat the insides and although it's recommended to put in a new plug if you are re-starting after "winterizing" the engine for long storage, they usually crank up easily. Maybe this might help the older engines? Luckily, if I'm way off-base here, Copey will help me find the folly of my ways...... Jon

Me too. The Marshall was also parked at the last turn to the finish and was on camera a lot and the chopper shots from above showed them running around the course. Pretty cool. Jon

I seriously doubt that this is a 2002, unless it's a mix-and-match bike which I would probably avoid at all costs...... The forks are the pre-2001 three-piece lower leg, for instance. Hey, maybe it has 2002 premix fuel in the tank..... Jon