h1 gearbox in h2 cases

[Davy Sprocket]

hi guys apart from larger bearings are the 500 and 750 gearbox the same does a 500 gearbox work ok in 750 cheers dave

[husson73]

you need to change also the primary gear on the crank and the clutch assy (to fit somes of H1) if my memory is right.

[Davy Sprocket]

thanks i think it would probably be the later ones that would fit

[malc87]

Apart from changing the gearbox bearing to a larger one the only other mod you need is to change the gear on the inner kickstart assembly for a 500 one so it match’s the 500 gearbox.
It will all work fine then.
Higgsy ran one in his H2C in his “ serious thrashing” days with no issues .

[doodah]

What effect does the 500 gearbox have on the top speed of the 750 motor?

[scouse]

What effect does the 500 gearbox have on the top speed of the 750 motor?

Very little

[Davy Sprocket]

thanks guys its probably easier to source a 500 change out all the bits--- than wait for 750 stuff to turn up!

[malc87]

It is
You will notice little difference .
I have spare 500 gearbox’s

[Davy Sprocket]

hi sounds good are they complete-- gear selectors etc im up in Scotland so guess postage req if an option?--- and price cheers dave

[malc87]

I’m at the TT,
Back next Thursday

[malc87]

Your existing H2 selectors and drum will work fine

[malc87]

I can talk you through it all properly when I’m back

[Davy Sprocket]

thanks Malc that'll be great been away from triples for a while bit rusty have a good trip cheers dave