Yamaha makes a TT660 dirt street bike for Europe, The top end came right off the TT660 for use on the Raptor, Except the top end on the Raptor was detuned 20% from the TT660. This is what I was told by a good friend that runs the parts room at Pelham Yamaha.

 

Your info is wrong. Yamaha based the motor on the tt they did not use parts from the tt

 

This has been discussed before....there are several 660cc bikes that used the same engine. The '01 Raptor has the exact same INTERNAL gearing as the streetbike counterpart. Few changes were made to the street bike engine for Raptor use.

 

Thanks for posting the correct info, I often wondered if it was true or not.