Has anyone ever had any problems with the gearbox? When my bikes crankcase was split open we found the edge of 3rd and 4th gear drive dogs had worn away to a taper and were thus were disengaging the 3rd gear when loaded. This was putting extreme pressure on the selector yoke (which had bent and had gouge marks on the side. Our only symptom of this was a lot of metal shavings in the oil filter. Bike supposively had 4000 klms on the clock.