more money, more unsprung weight, more suspension adjustments, if mounted on other than stock wheel not legal in superstock classes...
see the thing is i can get the 170 rear tire really cheap...and my question is would it really make a diffrence in the way my bike handels thanks
It'll make the bike steer slower. Whether this matters a whole lot depends on your situation. If you're close to running up front with the local SV hot shoes, bad idea. If you're 10 secs off the pace, less of a problem. It might even be a good thing if the cheaper tire lets you run more races and/or trackdays. If you switch and the rear seems to want to spin up more take a little rear ride height out.
I believe most modern 160's are technically too wide for a 4.5 inch rear wheel. Hence Honda switching from a 4.5 to a 5 inch wide rear wheel on the F3's, even though they didn't change the tire width. You should check the tire manufactures wheel requirements for the tire you want to run to be 100% certain. I ran a 165 slick on the 4.5 for all of one practice session, and absolutely hated the way it handled. It was a total pig. So now I run an F3 rear wheel, and it seems much better. The tire was very "square" on the 4.5, where now it appears to have a more normal profile. Of course, like whoever said, it's not legal in supersport classes now. Or more accurately, I'm not legal in D Superbike or C Supersport with this wheel. Not that that stops some people....
Oh yeah, here's an idea. Take your cheaply aquired 170's, and sell them at a profit to your street buddies. Tell the guys running 160's how much cooler their bike will look with the fatter tire. And tell the guys running 180's how much better their bike will handle with the slightly narrower rear hoop. Then take the extra money and buy yourself some real meats!
