Scooterotica

just had px 150cc rebored and after about half a mile down the road it was nipping (heat seizing) it kicked back up then did it again blanked auto lube off and i have been pre mixing dont no what to do next can any body help

Did you check its been done right, may be piston to tight in barrel if its nipping up so quick.

if it nips that quick you need top end off and a good look - check the piston to bore tolerances, clean the piston up, hone the barrel to correct tolerance and put new rings in

who did the work - reputable scooter dealer or local engineering firm - i have seen badly bored barrels that were oval and tapered.

best of luck

Check your circlips/wire on gudgeon pin have not come out

Yeh check the piston to bore clearance ..i once bought a new LML 150 top end (well it was in LML packaging anyway) from a dealer ,to fit to a px, stupidly i assumed it would be fine but it nipped up before i'd even got out of third gear on the first run.

Having checked everything else was right ,jetting ,leaks,seals ,i whipped it off and looked at it and measured the clearance, didnt seem right but still i assumed might be me, so took it to the local engineer and 2 stroke guru , he said there was practically no piston to bore clearance .

I would get it off get the feeler gauges out and measure it, can't remember what it's meant to be it will be in the haynes maybe or someone here will know , i think the best way to measure is up the side of the piston skirt with it pushed in a few mm from the bottom of the barrel..