Hey Bergbro,
4 failures in total, first 3 were 3rd or 4th dogs Ive beefed up the circlips stop discs, detent arm springs and reprofiled the shift star, since then no more missed shifts so this is the first tooth
all the grip of the paddle in sand and lots a torque. ever noticed how the big HP roadies have a real big pinion on the crank its to reduce the tourque that the box has to deal with. in oz some guys with tuned xs650s get special clutch gear and primary drive gears made up to do the same thing.
Ive just bought a complete hayabusa gearbox and clutch from ebay its clutch converted to auto and 4th 5th 6th are going to be the drivetrain for a lightweight "bitsa" bushmech engine, gotta have something to do to stop me watching telly
the gear that broke came out of another bike so i dunno its history, no missed shifts since it went in my tractor.
alternatively to going busa box I could have a new berg box properly heat treated cryoed and micropolished beacuse the gears are quite brittle and very poorly finished but I think at the end of the day the Busa box is the go.
as Dr-C and Smorgy have pointed out numerous times I should also have a cush hub or sprocket. Im getting there slowly,
tanks are more important ATM.