[Newell]

What is max tire width on an 18" stock rim? Looking at Bridgestone BT45, will a 130 fit or is a 120 max?

 

[LAYNFRM]

i don't know about 18" sportsman tires, but i've got a 140 s12 on my 18" for dirt with no clearance problems

 

[tallboy350]

I have a 140 perelli scorpion on my rear 18" rim. It's pinched a bit, but i've had no problems with it.

 

[maru]

Careful here. If you pinch this tire too much you will lose contact patch at ful lean, not gain it. The bt45 works pretty good by the way.

 

[96XR600r]

Running a 140 IRC street tire on my XR600 with the stock rear rim... It is pinched a bit and I cannot use about the last 3/4" of tread on either side due to the roll-over of the tire...

My buddy with an XL600 (stock 17" rear rim) actually has a tire that looks wider, but is a 130....

 

[maru]

Not being able to use the last 3/4 inch may not be that big of a deal on a street bike but the guy asking the question is planning on racing the thing. My advice is don't get too hung up on the look of a big tire, stick with something that will work. A tire pinched in that much is actully a smaller contact patch at full lean than a narrower but properly sized tire. Ask yourself, what would be the benefit of the bigger tire?