Hey, my GF just picked up a 2001 cbr 600 f4i, and the speedometer is reading about 25% lower than it should. She's been stopped now twice for speeding, and both times says that she wasn't. So I called up a cop buddy of mine, and asked him to clock me on her bike. Sure enough when I was doing 60, his radar said I was doing 82... now, is there a simple fix to this, something that I could check. Is her speedometer cable worn out? or is just a calibration that needs to get fixed?

Any help would be appreciated.

Thanks

 

Are the spockets changed? Try a speedohealer

 

I agree, sounds like sprockets have cahnged. A SpeedoHealer will definately do the job