Figured I could get a quick repsonse if I posted this real quick. I do not think the rim size in different from 01-02 to 03-04, but I could be wrong. Wanted to know before I get a new tire mounted and balanced on that sucker.
you can mount a 180 or 190 rear on the 03-04 models. Don't think the 01-02 model will accept a 190 rear. Think the 03-04 model rims are wider by 0.5"
ALL the GSXR-1000 models come with a 6" rear rim of the same size and dimension. A 190 will fit no problem.
The 750 and 600's come with a 5.5" rear rim (which you can also put a 190 on no problem too)