tony27

Leave the pads in place & use 2 screwdrivers between them to force the pistons back, if they aren't too far out they should push back fairly easily without tipping in the bores

Could be that your pads are getting worn enough that the pistons are staying out too much. I wouldn't try pumping the pistons out to lubricate them as you're more likely to end up tipping them when trying to push them back The way to see if the piston in the master is sticking is to remove the lever & rubber boot then have a look to see whether the piston is in contact with the circlip at the base of the master cylinder, give the piston a couple of strokes with a screwdriver to make sure it returns freely

Going on your description of the jet size & location the jets will be different shapes, the jet mounted in the float bowl will be round & the 1 that screws into the needle jet will be hexagonal, their numbering systems are different with 1 being diameter of the hole & the other being done on flow

The problem people have with their tanks including me isn't caused by the tanks being out of the frame, I struggled to get mine out. What happens is if you fuel contains alcohol like most does now the tanks swell, I run on a 50/50 mix of avgas & 91 octane which doesn't seem to contain alcohol & my new tank hasn't had any problems since although I haven't managed to do any riding in almost 6 months

Make sure there is no damage to either taper, if there is then a you'll need to remove it so the tapers lock together properly. A bit of fine wet & dry will work for the crank, using some fine lapping compound between the 2 parts in a twisting motion will match them up, don't go mad on it though as the flywheel will move inwards on the crank if you overdo it

Pilot jet is first place to look, the choke acts like a separate carb which is why it idled with it on

If the lever doesn't return by itself then it'll be the spring, you'll need the clutch cover gasket as well. The job isn't too bad, needs the clutch cover & clutch removing if my memory serves me correctly

The thread of the brake light switch is a standard m5 from memory, the adjuster it fitted into is either m7 or m9x1 from memory, easy to buy an off the shelf aluminium adjuster that fits from any number of dealers

Easiest to pull the rear wheel out then the 2 clips that hold the pads, don't touch the bolts or you'll dump the fluid out of the caliper & need to bleed the system which isn't fun Don't worry about using a torque wrench for the axle nut, just do it up tight without really leaning on it, you're unlikely to strip the thread even if you do get carried away

Pretty sure that direct injection is still banned in FIM competition which would prevent any manufacturer doing any serious development on anything other than commuter bikes. If memory serves me correctly the NSR500 that Ito raced in the 90s used a more basic system than fitted to the Ossa & it was far from perfect, the Bimota Vdue was developed with DI but ended up back on carbs when they didn't have the money to get the setup right The best part of direct injection is that the fuel is injected after the exhaust ports/valves have closed which means none escapes down the exhaust which helps with both economy & emissions. I'm certain the Motogp teams would use it if allowed for the economy reasons & the manufacturers would have plenty of knowledge through their car making tie ups

That's not a slight amount of wear on those gears, I see missing parts of teeth etc. What did they come out of?

I did the change to a 7kg or so lighter bike in 2000 with no loss of reliability & found that the lighter bike was easier to control in 99% of situations. I much prefer having a bike that I can ride as well at the end of the day as the start than 1 than wears me out, no way would I enjoy a multi day trial as much if at the start of the next day I was sore & tired from fighting with a heavy bike the day before Certain bikes do have problems but I don't think adding weight in the effected places would be possible without major redesigns & what manufacturer would do that not knowing if the rules are going to change overnight again Earlier on in the thread Motogp was mentioned as having had the rules changed for the better, have you seen how badly costs have increased since the change from 500cc 2strokes?

If you're still running the dellorto then a fuel filter isn't really needed as the carb has a screen behind the bolt when the fuel pipe connects to it, length of the pipe shouldn't affect how the filter works so your new filter may be a dud

You should be able to adjust the spring off for more sag although the photo on splatshops site of the shock shows less thread than the earlier models, get hold of splatshop about the recommended spring length when off the bike How has the damping adjuster been set?

Needle rollers have no place in linkages from a engineering viewpoint as the amount they rotate is minimal & they're designed to be constantly rotating, ideal is to make aluminium bronze(work hardens) or more commonly phosphor bronze(has self lubricating qualities) bushings of the same dimensions Doesn't mean I don't still have needles in my bike but I only because I've never gotten around to making up any at work

Is the noise happening when the shock compresses or returns to normal position, if it's when it returns to normal position then damping is too light & needs adjusting or a service, if it's when compressed it may be something completely unrelated like the stand

Look at the back of the cases for engine size, will start with st25 for a 250 or st29 for a 290. Topend end is only difference between the 2 bikes so engine & frame numbers are only a guide to what it began life as

Peter Boettcher is half the NZ importing team & is on here from time to time

Don't take it off the carb then, much easier to get on & off the airbox Pretty sure when I still had the dellorto fitted to my bike the jetting was very close if not the same as Copemech has provided

Sherco uses normal Dot4 brake fluid rather than mineral oil like the gas gas' use, completely different master cylinder internals in the 2 different brands of bikes

Different colours are caused by the heat that the exhaust gets to, when heat treating metal using a flame you can see the colour of the metal changing as it heats up & you use the colour change to judge when you're at the required hardness & stop heating

Isn't the renthal actually made by regina anyway? I used to use an o-ring on my jt35 in the 90s but since I've had shercos I find the better regina lasts well, a lot of guys use did mx chain but the 1 they really liked isn't available anymore

The thumb on the engine cases is standard for the early models, can't quite remember whether the front guard had any stickers on it but will have a look through my stuff from back then when I get home from work in the morning tomorrow The 99 & 00 bikes had laquer over the top of the stickers, think you couldn't buy the stickers seperate

Just the o-ring, quick job to do. May as well do the 1 where the midbox joins the muffler at the same time

Looking at the photos of the thorns & your description of what happens I'm guessing that Michelin x-lites aren't used there