Maybe gearbox breakdown

[johni]

Hi I got a problem, when i am riding normaly there is nothing wrong, but when i dragrace the vmax it is like the transmission is jumping one time at about 6k-8k, it happens in all gears, i have changet the final drive but it is stil the same, is the gearbox broken?

 

[gamorg02]

Hi I got a problem, when i am riding normaly there is nothing wrong, but when i dragrace the vmax it is like the transmission is jumping one time at about 6k-8k, it happens in all gears, i have changet the final drive but it is stil the same, is the gearbox broken?

what do you mean it jumps? what yr max?

 

[johni]

It is a 1986
I meen like if you have an chaindriven bike and the chain jumps the sproket one time under hard acceleration

 

[maleko89]

I would check both ends of the drive shaft. Perhaps it's slipping there.

 

[gamorg02]

sounds sort of like the 2nd gear issue but all over?

 

[johni]

The driveshaft looks like new and i have put on another differential on

 

[maleko89]

How about the u-joint?

 

[johni]

Year like the 2 gear but in all gears

 

[johni]

the ujoint looks great

 

[maleko89]

If it's jumping out on all gears either the tranny is really trashed or it's the clutch. I'd start with the clutch since that's easy to inspect/replace.

 

[johni]

Ok here is the hole story 30 days ago my max was a 1992 big cc 151 rearwheel hp, then the dam thing blewup (crankshaft exploded) then i foundt an 1986 vmax and took the engine from that one and put my dragracing clutch on it so i dont think it is the clutch