Scooterotica

just rebuilt a vespa vba 150 engine and having problems with the clutch.
when you compress the clutch the kickstart will go slack like it should but when the bike is running it will not clear to select gear it just lurches.. when engine is off bike in gear the clutch will not clear to freewheel either.. new corks and steels in the clutch?? any ideas??

seems to be stumping quite a few people this one........

col, i had this problem on a vbb i did the engine for a few years ago, it would seem fine with the engine off, clutch in, depress KS lever, in and out of gear , etc. start engine, clutch in, let it out, the bike lept in the air! did everything, even renewed the cush drive springs. had the clutch in and out a dozen or more times. in the end , paul from motech said "is it the correct clutch ?" showed him , and after a rake around he found me an old but good one from a vbb. put it in, and it was fine. dont know why, must have had a dodgy clutch put in in italy, and that was why it was a "barn find" over there years later. i just assumed it was original.

hello mate have tried 3 different clutches in now witht the same result... vba clutch, vbb clutch and px clutch... just been reading a thread from another forum with a guy with the same problem and i think its because the space washer is missing behind clutch but this is third engine i've dismantled with no spacer in there ?? all working engines ??

col. if theres no spacer washer, the thrust bush wont depress the clutch, or if too thick a washer, it"ll just drag/slip. SIP do various thicknesses. i"ll have a rake in the shed of doom and see if theres one knocking about in a box of bits you can have.

I had this problem on an old Vespa years ago built from a box of bits and there was no spacer in the box ,so not knowing there should be one I fitted motor and had the same problems.After lots of head scratching I realised it needed one

Are you using the same clutch cork plates and steels in each clutch you try? If so try changing them cos I fitted new plates in a rebuilt engine last week and had same problem. Measured the plates and steels against another set and they were a few mm thicker which caused this problem.