Hi,

Could someone advise please, are 199a and 199b cylinder heads a straight swap?.

Haven't tried ... but:

- the 199b had has no cylinder gasket, the 199a has a thick copper gasket.

- the 199b has a 85mm bore, the 199a has 83,2mm.

the copper gaskets like these.

the 199A and 199B won't fit each other has pschrauber says. the 199B has a raised barrel and locks into the head into a groove the 199A is a flat face on barrel and head.

Thanks for that guys, I've been offered a 340 motor without a head.

After reading your replies I managed to find some exploded diagrams and it looks like the 340 head is a 325 head with a relief machined to take the 340 liner.

Can anyone confirm this please?.

In fact, it looks like the 1975/76 type 350 sherpa head has the same relief?.

Edited August 27, 201412 yr by bulltaco340

am not sure on that 1 mate but i do think some off the 325 (350) did have the same groove in the head if so they may fit the 340 if not i should think it would be hard to find a 340 head on it's own. i have a 350 spare engine 199A but it wont fit a 340 all the 350 engines iv'e had have all been the same. with the copper head gasket iver come across 1 with out. unless it was the early 350 that had the raised barrel. is the 340 motor to put into a 199B frame? or just as a spare?

A bit of both bondy, I've got a spare 199a without an engine and thought I might play around building a modified bike over the winter.

I wonder if anyone has contact details for John Collins who has (or used to have) a trials used spares business?.