Gearbox tweaks help appreciated.

I will soon be rebuilding my 175 engine, I am trying to get on top of all the mods and tweaks in the gearbox, can any one tell me what the modification to the gear selector
Spring and where I can get the up rated spring from?

not my subject, who can help colin????????????????

Derek

Colin see both 'Mikes gearbox tips' and also 'General tuning'(by Martin Elliott this was Section 1
from origanal tuning manual. Ref spring I've never replaced one but have 'packed the spring as tuning manual.

Mike

Hi Colin pm robbie brown his an expert in gearboxes after last year.

Thanks to Mike and Ian

Hi Colin
How did you get on with the gearbox, have you started assembly yet, I'm currently assembling my 175cc has a std GT alloy barrel and original not a btw copy,
my frame is now finished and it has a plunger set up, much modified by myself, but colin there is a very good page on this forum, by Mike Powell on gearboxes, he has written under technical drop downs, some very useful information, but please be careful when spining the gears in the lathe, make sure you oil them as free wheeling will give quite a lot of wear, not on the shaft but on the layshaft slider gear that is hardedned to a lower spec than the main shaft, this is so they wear out in preference to the mainshafts BSA did not do everything wrong, well not in the factory, only in the board room!.

what we did for this was turn a slow taper shaft then push the gear on tight gives a better indication, without having to free wheel then.

Kind and best regards Terry