G'day all,
John O R, primary ratio is 1.88 : 1 belt with diaphram clutch. 7500 rpm if balanced & lightened right.
Richard L, for racing or very hard riding only, 9 studs + 4 through studs 5/16 at cases to 3/8 at head.
Iain, also have a 9/16 nut attached to bottom of frame rail with a bolt that screws down onto 1/2 plate over rocker box.
A10Boy, No BS here.
Cheers
PS still can't fix nerdbox to do pics.