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The spring pre-load is adjusted using the hex nut (22mm) on the RIGHT HAND fork leg. counter clockwise - less pre-load. clockwise - more pre-load. Central brass screw right leg (brass) - Rebound adjuster Central brass screw left leg (brass) - Compression adjuster Image Here: LINK

What a fantastic article and very true to the man. I was actually at Piber's house the day that Jordi Pascuet rode the waterfall (twice) - first time he was a little slow and ended up with wet feet! Second time was perfect - lots of laughs all round. Thanks so much for the great work you do with your site, and the depth you have gone to, showing such dedication and hard work for the benefit of Trials riders around the globe. Well done, and a fine read. Narcis next?

Download this from the Hell Team tech page and read it BEFORE you do anything. Specifically the Dellorto carb manual. It will give you a good understanding of how a carb actually works - then you will know what to blow out, and more importantly WHY. https://www.dropbox.com/sh/day2hdj2qwmewsm/AACZ_wRKN-1lwzo3FU-Jb89sa/Carb%20tuning%20info?dl=0 It's incredibly straight forward once you understand how they work. No rocket science or black art needed.

There is a specific Keihin inlet manifold/red block available as a OEM part. (part #2303321) Apart from the PWK carb, the parts required are throttle cable, and this inlet manifold/reed block.

Neutral

The Gas Gas Fibre discs fit, totally interchangeable, but the Gas Gas Steel discs do NOT. (distance between "posts" is different). You can source the Steels from a JGAS dealer/importer or S3 also have them. The JGAS steels standard are 1.5mm and the Gas Gas ones are 2mm now days, so it takes a bit of fiddling with plates if you want to use GG fibres and get your clutch stack height correct.

To put a few of you straight Gubian was in trouble because he had a massive head on crash with another rider just before he started day 1. He was belting back from the practice area at a fair old clip and T-Boned Australian GG rider Boyd Willcocks who was riding out to section 1 - it was a big one! i spent quite a bit of time replacing bent and busted bits on Boyd's 300 in the GG pits, and I know Loris came off worse. Brownie was sick. Neither situations had zip to do with bike reliability. Period.

Hi Dan I would suspect you have managed to get the bearing plate (MT2803320140) and/or the clutch bearing disc (MT280232043) under one of the clutch fingers (MT2800632070) on re-assembling the clutch. This can unfortunately sometimes happens when working on the bike in an upright position allowing the fingers to fall away from the hub, and as you push the side case back on the plate can get "behind" one or more of the fingers. The best way to work on these motors is with the bike lying on it's left side - then the fingers naturally stay flat. Use a small bit of assembly grease to hold the clutch bearing and plate to the slave cylinder piston when putting the side cover back on.

The Sidi boot uppers are not leather, they are a synthetic called Tecnomicro. The only leather on a Sidi is the suede section on the inner calf protection area, so I'm not sure if the saddle grease is the right thing for synthetic leather found on the Sidi's. From searching around at Dr Google it looks like most synthetic leathers use a specific treatment formulated for that material.

And also allows for a bigger airbox.

It's a very common problem with that Yamaha motor - there was a heap of posts on ThumperTalk about it in the YZ250 configuration. it's not just a Scorpa thing! Scorpa improved it in 08, but still with some drag issues. This is the setup from the italian X4 Team: Clutch mods for 06/07 only Scorpa SY250F, 2008 SY250F do not need any modifications as a different stack is used. The stacking of new clutch discs can improve the sensitivity and avoid possible clutch drag. Here, below, follow the order to insert discs: - Disk Friction 3XJ-16321-00 5NL-16325-10 5NL-metal disk- Aluminum spacer (Scorpa OEM plate) 5NL-16325-10 5NL-metal disk- - Disk Friction 3XJ-16321-00 5NL-16325-10 5NL-metal disk- - Disk Friction 3XJ-16321-00 5NL-16325-10 5NL-metal disk- - Disk Friction 3XJ-16321-00 5NL-16325-10 5NL-metal disk- - Disk Friction 3XJ-16321-00 We found a little shim washer (cant remember the thickness but it was quite thin) placed on top of the hub towers, in combination with this clutch plate combo above did the trick. You will have to do a bit of trial and error to get the right shim washer thickness to get the right balance between slip and drag, but it does work. Check the ThumperTalk Forums - search under $2 fix for Yamaha clutch YZ250.

Hi Sam It can be done from the top of the cartridge, but in our shop I prefer to disassemble the forks completely to check all the parts, and make sure nothing is broken, bent etc. The one sure way once you have the cartridge out is, on the bottom remove the little spring clip. You can then remove the the slug and small bottom out spring (that's what we call them anyway). This will then allow you to push the damper rod and piston out and clear and allow you to get all the old oil out, and fresh oil in. (have a good inspection while it is apart). Fill it right up with the cartridge upside down, and slowly pull the piston back in just enough to clear the small holes in the side. Oil will get every where so do it gently. Then put back in the spring, slug and circlip and re-assemble. It's a bit of a messy job, but should sort it if you make sure there is no air trapped. Don't compress the damper unit at all, until after it is re-assembled in the forks, and the leg is full of oil.

Sam123 The "clunk" on extension means you have air in the right leg damper cartridge. (95% of the time). This is a reasonably common issue with Marz 40's. There is a few ways of doing this, and not all of them are easy to explain on a forum, but l'll give it a try: Remove front wheel loosen top cap after slacken bolts in top triple clamp. (i have special tool for this with the pins set to match the holes, but they are usually not hard to undo as long as the triple clamp is not clamping on it) remove fork completely from triple clamp. Undo top cap and lower upper fork leg in lower leg. remove top cap (need to pull down pre load spacer to access removal) cap and spring can now be removed undo bolt bottom of fork leg remove damper unit Now you need to refill the damper unit COMPLETELY with oil (5W) - make sure there is no air at all in unit before re-assembly. Check out the exploded parts diagram so you can see the internal parts of the damper unit. Prime this cartridge so it is full of oil and no air bubbles are present. Reassemble and fill with 5W fork oil so when the upper leg is pushed all the way down, there is 160mm of clear space (see diagram available on GG USA sight - tried to download my copy but it was too big) at the top.

Jitsie sell 1.6mm plates if you need them to achieve the stack height you desire. Alternative fibres are available from Sureflex, Adige and S3 (complete RACING kits - Hoerbiger friction discs) The thicker disc does go in first (engine side)

The rider is Australian Jack Field. He recently just competed in his first big EnduroX in America, The King of the Motos, decided to ride his standard Gas Gas Pro 280 at the last minute (leaving the KTM 300 in the pit garage), and came 7th outright over the 160 mile course. He is also competing in the 4 round X-Games series kicking off in Brazil, and the Geco AMA Enduro-X series in America this year. His bike skills are amazing. Check out a quick clip of one of his small shows:

Well we have a Gas Gas TXT-E already down here in Australia, so they are available already. 10kw motor, 20nm torque, 62kg. Battery indicator. And it does have the clutch kit installed. The clutch kit works on a modified AJP mastercylinder that operates a linear potentiometer. The clutch release ramp can be modified with the programmer, as well as other parameters like throttle ramps, engine braking etc. Works really well.

Having worked on plenty of these motors i would say go for it, they are an absolute joy to work on. Very straight forward, simple design that needs no special tools except the flywheel puller. To pull the motor take the clutch side cover off and cable tie it to the bars (no need to disconnect the clutch hose). Take the flywheel off and remove the stator and cable tie that to the left side of the handlebars (no need to remove wiring). Remove the tank, airbox, and carby, then pull the motor. It's pretty obvious and straight forward. Once you have the motor on the bench and start to dissassemble just be careful to take note of all the shim washers and thier placement. The left side case will come away from the right side case with the gentle use of a soft rubber mallet. All the gear cluster and crank will stay in the right side case. To remove the bearings from the cases pop the case in the oven on a low heat (120 - 150 degrees) for 15 minutes and they will just knock out with no force at all. A good tool is a can of plumbers Pipe Freeze. It is an aerosol can of basically pure freon, and works great for quickly shrinking parts (or chuck them in the freezer for an hour or so). Just always think about using either heat or cold to remove parts. There is no need to force anything on a Gas Gas motor. PM me if you need any specific advice and i'll walk you through it. Regards

C4

gwhy i should have premised my comment with the fact that we have sold all three brands and models of bikes in our business, and we still sell the Mecatecno and GG , so we know all 3 brands pretty well.

The Mecatecno is not a "copy" of an OSET it is a different manufacturer doing their take on a kid's electric trials bike. They have some differences, and improvements, over the older OSET design. The Gas Gas kid's electric bikes are EXACTLY the same as the Mecatecno's , but with GG branded, and coloured plastics and stickers. They are made for Gas Gas under license by Mecatecno. The only difference between these two kids bikes is cosmetic.

Check that the friction spring (the circlular spring with the "U" shaped tang), not the kickstart spring, has enough tension on it. When this spring gets "old" or "soft" it does not grab the quadrant gear with enough force to help it up the kickshaft spline. You can kick to your hearts content, and it will just slip on the quadrant gear.

Check out Jack Field !

Hi Does anyone have any contacts for Trials Clubs, or riders in Mainland China? We have been asked to go over and do some demo's at a Motorcycle Show, and would like to involve some local riders ..... if there are any. I know the cycle trials scene is happening over there, but a Moto Trials club.... I don't know. I recall seeing some photos of a trial maybe five years ago, but I could recall if it was mainland China or Hong Kong, and I now cant find the reference. All help appreciated. regards

I have come across this problem once in our workshop and the Pro in question had a wheel spacer intended for an AJP set up on a later model bike with Formula brakes. (there was a bit of wheel swapping at the WTC in Australia and spacers got mixed up on the bike in question). The wheel spacers are different thicknesses for AJP and Formula setups. This allowed the axle to sit out too far from the swingarm, so when you tightened the disc side axle bolt it just pulled up against the axle rather than the swingarm. If you fit the axle and S3 snail cam as you would from the sprocket side, then it should be a fraction short of sticking out from the right edge of the right swingarm leg. If it is proud or flush of this then you need to space the axle to the bikes left - either with a slightly thicker wheel spacer or a shimming washer. Basically it probably means the snail cam you fitted is a fraction thinner than the one that came off it causing your problem.

Gassers like good clean head! An excessive build up of carbon in the combustion chamber will cause a "lean knock" sound, but it is actually a slight pre-ignition. Remove the head and clean the piston crown and combustion chamber, most of the time that is all it will need.