Hallo all you Bultaco Specialists.

Got a M8 over here who is rebuilding his 199 1978 Bultaco. (His description!) He has heard of some clutch mods ..."which evreybody did in the 80s..." which may use some Hoinda (!?) parts. Anybody know something along these lines?

Lee

Maybe there was something good done with Honda plates back then in Bultacos but the hot setup now is to use a Barnett friction plate kit in Bultacos. This allows the spring preload to be reduced, lightening the lever pull.

Your mate may have heard of mods to some Montesa Cota clutches that used Honda friction plates to improve the action.

Where can I get the barnet frictionplates. What springs can then be used?

Lee

Barnett clutch plates are available through motorcycle shops around the world. They are made in USA.

Use standard Bultaco Sherpa clutch springs.

Stiffer clutch springs are also available from Barnett if you have a hotted-up 360 Pursang with road-race gearing that is having problems with clutch slip in top gear.

you can remove 3 of the springs, cup etc in the clutch basket

this makes it lighter

the clutch dosn't slip

i have two 199 one day i will rebuild one

Seeing that you are asking about the clutch springs, I am guessing you have not actually looked at the M199 clutch yet. The spring preload should be adjustable on that model Sherpa. Each of the six springs has a nut which should be be positioned to ensure that the plates move apart in parallel as the clutch is disengaged. The nuts are also used to adjust the clutch spring preload.

When you assemble a Bultaco trials clutch, a good starting point for getting the clutch spring preload correct is to adjust the springs until the (pre-lubricated) clutch is able to provide enough drive to allow the kickstart to turn the engine over compression without slipping.