See my threads under "catastrophic transmission failure". No need in repeating the saga here.
However, I did learn something from my mechanic a few months ago. After many failed attempts at repairing the transmission, my dealer finally conceded to complete replacement of the transmission. Turns out they had an upgrade kit in stock for an upcoming rebuild. The guy totaled his bike before it could be installed. Dealer decided to do a complete replacement and compare the parts to see if there were any differences.
When they tore down my perpetually failing tranny and compared it to the complete replacement kit, they found one VERY IMPORTANT difference in addition to the gear set, dog rings, shims, bushings etc.
The star wheel on the outboard end of the shifter drum contains a little ball bearing to index the star wheel and prevent back rotation under torque load. When you shift the linkage, the ball is supposed to drop into the slot and prevent the whole arrangement from indexing any further until the next shift cycle. The upgrade kit contains a SMALLER BALL BEARING than the original setup. The mechanic theorized that the larger original ball was not allowing the linkage to fully seat. Under heavy acceleration, the torque load forced the shifter drum to back out of position!
This is a major aha moment. It confirms my theory that the shifter drum was backing out of position (probably from the helical cut on the newer gears).
So there you have it - - 9 months of headaches, downtime, and rework for a $0.50 ball bearing! If my dealer had done the FULL upgrade instead of a piecemeal rebuild, I think my bike would have been in operation by September instead of February.
Anyway, I'm happy to report that I've put on 3500 miles since the CORRECT upgrade kit. She snicks right into gear and handles WOT shifts with ease. Amen!