Sherpa Rebuild

[BOGWHEEL]

Hi all
Can anyone advise on whether bearings and seals for a sherpa are available as stock sizes from a bearing shop please?
Prices from the spares guys are a bit scary.

[David Lahey]

From memory last time I did a Bultaco motor (I assume you are talking about the motor) I used a seal kit from a Bultaco specialist and the bearings were mostly from the bearing shop.
I discovered later that one of the Bultaco crankshaft seals is the same as one of the crankshaft seals for a TY175 motor. Can't remember which one offhand.

[BOGWHEEL]

Also - can someone advise on the correct piston clearence for a M199 please (84.2mm - 340cc)
thanks

[David Lahey]

Ideal piston clearance is different for the different alloys that pistons are made of because different alloys expand at different rates per degree. Your piston kit should have come with guidance for the correct clearance.
An old rule of thumb that may or may not apply to your piston is for a rebore clearance of one thousandth of an inch per inch of piston diameter.