180 or 190
 

From what it sounds like, most people seem to run 180 back tires right? On the 2000 R1, a 190 came stock, and that is what is on it now. Why the difference, does it change much, etc?

190 refers to the rear tire width in mm's. A 190 is slightly wider than a 180. I'd say keep the 190. A 180 will give you quicker handling at the expense of some traction, you need traction more than handling on that bike. At least for now.

The explanation of the rest of the code:

190/50/ZR17

190 is tire width,
50 is aspect ratio at max lean
ZR is speed rating
17 is rim size.

Yeah, i knew what it meant as far as size. Just wondering if one was better than the other or what.

I'd stick with what came stock, in this case the 190.

fair enough. After looking at my buell's 120/60s16, That thing is absolutely massive.

i'd go w/ 180, personally

For the Busa...

Tires Front: 120/70-ZR-17
Tires Rear: 190/50-ZR-17

I think mine might be the same ambly. I will check after I get out of a meeting.

Negative. You lose more of a contact patch which is needed on the liter bikes to handle the power delivery. In fact, a lot of 600 and 750 owners/racers will go up to the 190 for that reason. So they can get on the throttle quicker and harder. They just have to set their suspension up to compensate for the rear being raised more because it's a taller tire.

So stay with the 190, T. It's what is meant for that bike.

I was talking to some guys on r1-forum.com and they said some had tried a 180 but it didn't make a noticable difference in turning. They said go with a 190/55.