Depends on the shop and if they have to open the transmission. That requires splitting the cases... I would say a few weeks for parts ordering and technician time. I know thats probably not what you want to hear but splitting the cases and ordering parts can take time.
^True this. It looks like splitting the cases is required for access to the shift forks. Hopefully the problem is one of the things that can be done with the engine in the frame. From the service manual...
- Misadjusted clutch cable
- Improper clutch operation
- Improper engine oil viscosity
- Damaged or bent shift fork
- Bent shift fork shaft
- Bent shift fork claw
- Loose shift drum stopper plate
- Damaged shift drum guide grooves
- Damaged or bent gearshift spindle.
The only thing here that requires engine removal and case splitting is the damaged or bent shift forks.