torch
Well-known member
Power is the same I believe, at a claimed 141.5bhp. That didn't change until the 2013 increase (by which time the dang thing was 116lbs heavier). Even between the 2003 and 2006, the Gen1 is 61 lbs lighter. Secondary reduction gearing was changed by 1 tooth (Gen 1: 35/36 x 21/27 x 33/9 or 2.773:1. Gen 2: 35/37 x 21/27 x 33/9 or 2.698:1 and wheelbase lengthened 1".
Also, I think it was 2004 that Yamaha changed the throttle body ramp to be less linear, so it was less aggressive coming off idle through cruise, increasing the rate as one approached WOT. That doesn't really affect the overall performance, but it does change the throttle feel -- the 03 feels snappier coming off the line because you don't have to twist your wrist as far.
Also, I think it was 2004 that Yamaha changed the throttle body ramp to be less linear, so it was less aggressive coming off idle through cruise, increasing the rate as one approached WOT. That doesn't really affect the overall performance, but it does change the throttle feel -- the 03 feels snappier coming off the line because you don't have to twist your wrist as far.