[Resolved]  Yamaha — very poor engine

Address:

Kottayam, Kerala

i hav a yamaha r15 and its done abt 39000km and it is having engine complaint. it it said dat its gear shaft is worn out and need to replace the shaft.
yamaha sayin that its bcause of my over sppeding.. is r15 for slow speed economy ride? if so wats the racing DNA? ive done regular servicing and oil change. only changed rear tyre to 130/70-17 pirelli.