motorman

Thanks for the info , mine is fitted with Motoplat , haven't got round to changing the carb jetting yet. will let you know the result, Cheers Robin

Hi guys, I'm tearing my hair out here ! Have a 77 Ossa MAR 250 which won't rev out. I've tried everything plugs , carburetion , cleaned the exhaust, sent the Motoplat unit away to Spain for repair and testing. Engine is totally rebuilt on new seals and bearings. Everything in tip top condition , but it will only run cleanly to about 3/4 throttle and then misfires and won't rev out. Any ideas ? Cheers.