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Chris tells me that his peg placement was dependent of several other mods he did: "Critical was the lengthening of the swingarm, cutting the snailcam plate forward of the axle hole and adding 1.5" long, 1/4" thick plate and TIG welding. Just behind the steering head, hacksaw 1/8" out of the horizontal smaller tube below the backbone. Fit tie downs between the left and right side of the axle and the footpegs. Tension them Heat the backbone just behind the head. The tie down tension will pull the horizontal tube tight and bend the backbone. Reweld. The next mod is done to handlebar placement. The TY bar clamps are angled back. Very old world. Reposition? The clamps could be cut to be parallel on top as with modern bikes, and lower handlebar front edge should intersect the back edge of the fork tubes. With the other mods done, use the G-Gs as a reference for where the pegs should be in terms of percentage of space between peg centerline and front and rear axles. Also follow G-G, trying to get the pegs as low as reasonable. The TY pegs are goofy high with respect to the bottom of the skid plate. The G-Gs are so low the pegs are always scraping on things, and the bottoms of the peg mounts are below the plane of the skid plate. I'd also toss the Yamaha method of mounting pegs and not use the stock pegs and go modern, using u-mounts and modern, wider pegs. I'd probably create a plate to weld the u-mounts to, then weld all that to the frame. It's better for pegs to be out more anyway." His idea to use a modern bike for measurement to get ideas as to what direction to take makes sense. Jon

I sent an e-mail to Chris as to exactly what he did with the pegs and will report what he says. Jon

Be sure to replace the gear/shaft along with the split needle bearing. The floating gear's internal bore is essentially the outer race of the bearing and if damaged at all and not replaced will damage any new bearing. Jon

You might want to pull the M/C apart and check the seal/bore carefully for damage. Jon

If you just went up and down the street, you probably had enough air flow through the radiator to keep things cooled off. The fan usually operates when the bike is moving slow and has some load on the engine, like riding a section. Try a slow ride in the driveway to see if it comes on. If it was working before, it probably is o.k. now unless you moved the wiring somehow and maybe pulled a connection apart. The thermo switch can be tested in a pan of water on the stove, using a temp gauge and electrical meter to check conductvity between the two wires when the temp goes to above 180 degrees (82C) +-. The thermo switches are pretty simple and usually are quite reliable. Most of us use a 12V car battery to test the motor as the full voltage gives us an idea of how strong the motor puts out. Jon

Marks are o.k. The problem lies in a small amount of metal in the bore sticking up above the surface. That will force the ring to ride up on the metal and move back into the groove/land and allow exhaust gases to blow past the ring on either side of the protrusion. This can lead to local hot spots, distortion and, at the least, a loss of compression/power. Jon

The grey cast plug looks like it was run in a cylinder than had coolant in the combustion chamber. The plating is somewhat harder than the piston so pistons wear faster than the bore. The bore is plated with very fine Silicon Carbide particles imbedded in a Nickel matrix. The pistons also contain Silicon Carbide, usually around 10-17%. So, you have a ceramic coating in the bore and ceramic in the piston. It's difficult to tell from the photo, but if it's piston material, you may be able to remove it with Muriatic Acid (used in swimming pool care). Obviously you should treat Muriatic with the same respect you would any strong acid and take appropriate safety steps. Scotchbrite probably will not remove it. You could try some 200-300 grit wet/dry sandpaper and water to do it but be careful to only remove the piston material. 11.5-13 Nm is the torque setting for the head capscrews. Jon

Light brown is good. If it's coolant leakage, you should see small droplets down inside. Did you drain the carb any try fresh premix and a new plug? Jon

When diagnosing problems, always start with the more simple, less invasive things. Make sure the overflow tube is not crimped. If the tube is routed over the crossbrace, the tank will squash it, allowing excess pressure to build up in the cooling system and force coolant past the W/P seal lips. This could save rebuilding the W/P. What type of sparkplug are you using and what does it look like when you take it out? If you can give an idea of what the engine running conditions were when you shut it off really helps to intrepret the plug condition. Jon

My first guess would be a damaged inner o-ring in the head, which would allow coolant into the engine and cause loss of power and cutting out. The coolant in the trans could be coincidental to the o-ring problem but also could be caused by a crimped radiator cap overflow tube, which would force coolant (due to excessive pressure) past an otherwise good W/P seal. Jon

I like the clear, in-line, cone-shaped sintered bronze filters and use them on every bike. Keeping in mind the disk filters on the carb work for small birds and rocks, it takes an additional filter to keep out grit than can easily clog a pilot jet that has a .014" hole in it. You would be surprized at the gunge than forms at the bottom of storage tanks and old gas cans. Jon

Standard is 11/42 or 11/41. A lot of riders run the 10/42 combination and it seems to meet their needs. Jon

The GG's are designed to have a certain amount of clutch drag and the transmissions are also designed to stay in gear ( which is why you should use the clutch when shifting ) . This makes finding neutral stopped in gear difficult and with a little practice you'll learn to shift into neutral just before stopping. Jon

Try: http://www.trialspartsusa.com/tech.html and click on the link- "GASGAS Pro Technical Bulletin", that might help. Jon

Be sure to actually test them by riding section type terrain. You can't really tell by changing the adjustment and pushing up and down on the forks like most rider's think. They make a bigger difference at a higher speed/movement of the fork leg and shock shaft. Jon

At 182 lbs and a beginner rider, the stock springs should work for you. You can stiffen the front by making a preload spacer about 10mm longer than the stock one in each fork. Since it's a used bike, you will want to refresh all the fluids and lube all the necessary points (assume that the previous owner did not do anything just to be safe) including the rear suspension dogbones. The front forks take 300cc's of 5 weight fork oil in each leg. Jon

How much do you weigh? The knobs are for fine-tuning the suspension damping, black/left for compression and red/right (red=right=rebound) for rebound. The 02' forks work well with the black all the way out and the red all the way in (bottom the screws lightly so as to not damage the internals). Jon

I have both and they are excellent. You will need to get an "all region" DVD player that will play both PAL and NTSC. Most of the good Trials videos are in PAL format and a player that plays both is well worth it. Amazon carries them but I bought my DVD players locally. Jon

Adrian at LewiSport will know what to do. I've measured piston/cylinder clearance at .0015/,0020" on the new bikes and I think the A/B/C/D difference is .05mm. They match the cylinders to the pistons at factory assembly to get the correct clearance as Trials engines are very closely fitted compared to other competition engines. Cheers. Jon

If you check the top of the piston crown, you'll see a letter (A,B,C and sometimes D). For a well worn cylinder, you can usually order the next larger size. For example, if you have an A piston, you would order the B piston as a replacement. Check the cylinder, often on the base gasket sealing surface, and it also will have a letter to correspond to bore size. Unless you are a master machinist (which you may be), because of the close tolerances involved (and the wide array of rider's measuring talent), it's probably a safer bet to order the replacement piston by letter/bore size rather than measured spec.'s. Jon

As far as I know, the Reiger is for the Race and Raga models and an aftermarket shock for the regular line. The photos I've seen is that Raga uses the Reiger. I've had a ride on a Raga Rep with a well set-up and broken in Reiger and it is an amazing shock, very impressive, even compared to the Ohlins. Jon ps. "I realise that very little of the pro's bike content make it to market"- My experience is that, as far as at least the GasGas is concerned, most of the Pro's bike contents make it into the production bikes.

It would be hard to find better representitives of the sport. Jon

Yep. That's what the arm felt like after an hour or two with some of the old clutches. We run our clutch levers on the left over here as a tribute to where Trials began.... Jon

You can make a small plate with a slot in it (the width of the damper rod) to slide under the jam nut when you pull down the spring/spacer. Assemble the fork and leave the upper tube unscrewed from the top cap, tilt the fork over slightly and slowly pour the oil through the spring coils into the lower leg. Jon