DTDan

If you have just rebuilt the engine and done nothing to the carb the problem could be elsewhere. I'd suggest you check for airleaks - misfitted gaskets and leaking crankshaft seals can cause these symptoms.

Yes people i now realise its an earlier cylinder and no good for my application but has anyone ever bored out a 125 cylinder to nearer the 200cc mark ??

Its not an idea its a fact ! i always use this method and providing you keep the revs fairly low (3000 is fine) and select without forcing, the clutch free's off. As for damaging selector forks, guide pins, selector drum etc - you must know something i don't because in the 15 years i've been working on 2t 125cc engines (on road and offroad) i've never seen this happen ! As with most things in life there is more than one way of obtaining the result, my way works for me although i would agree your method is probably more suitable in this instant (if the clutch is at fault)

Thanks for the comments guys, found some time to get out in the shed and have a close look at the two cylinders tonight, it appears they are completly different the 125 has no provision for the reed block where as the 200 does - im thinking it must be off an earlier bike and as i was given it years back and told it was off an dt200 thats all i have to go on ! Which brings me round to thinking would it be possible to remove the bore liner from the 125 cylinder and have the cylinder its self machined out larger to fit a bigger liner ?? Has anyone tried this before ?? Cheers folks. Dan

My Dt also does this the first time i run it after its been standing a while - i tend to keep the rev's up the first time a select a gear after that its fine (make sure you apply the brakes before putting it in gear though !)

Yes mate im aware of the kit but i have a dt200 cylinder and head sitting around - a hell of alot cheaper and more cc's

Hi guys, i've just joined here after recently buying a dt125r (1998) and was wondering if the dt 200 cylinder and head assembly would bolt straight on the 125 crank cases, has anyone done this before and would it be possible to use the standard 125 conrod with the 200 cylinder and piston. Cheers in advance. Dan

Hi All Having just brought myself a '98 yam dt125r i thought joining up here would be a good idea ! Had the odd bike or two over the years but really fancied another 'stroker' for green laning and pottering around locally on. Anyway i look forward to learning a trick or two from the site and wish you all happy safe biking. Stay upright (ish) folks ! Dan