Need rear tire advice

[Yoda]

I almost wiped out a couple days ago and realized that my rear tire is overdue for a replacement.

I replaced the front tire a little less than a year ago with the stock BT-45 and have been happy with the performance and wear so far. I think I'm gonna go with a BT-45 rear as well but I kinda want to try a slightly wider tire (specifically 140/70-17) does anyone know how that affects performance?

(I'm also open to other recommendations for tires.)

At this point I mostly use the bike to commute to and from campus (about a 10-15 min. drive).

Thanks

[EdChen]

A matching rear tire is probably a safe bet, especially for easy commuting. The 140/70 is about 2.3% larger, or .55" larger OD. It'll raise the rear end about .275", which is probably not noticeable. It also act as if you've geared up slightly, which will yield worse acceleration, but lower rpm at the same cruising speed. Also, the GS500 supposedly handles best with the original sized tires, but again, for commuting, you're probably not scraping pegs. It's all very minor and probably barely noticeable. Go for it. 

Check this thread out: http://gstwins.com/gsboard/index.php?topic=62700.0

[Janx101]

I've got a 140/70 sport demon (with worn out centre! Needs replace now.) .. if you only commuting short distance and don't get out into spirited roads/twistys much then fit a COMMUTER type tyre for better longevity... but if you truly do get out and have fun leaned right over get the sports demon or similar for the extra bit of grip!

[Janx101]

... and whatever you get, check pressures regularly! .. safety and dollars are involved!

[Yoda]

I mostly do short distance commuting but when I have time to do like to do a little more spiriting riding. I think I'm gonna just stick with the BT45 to match the front and I might as well try the 140. Probably wont make much difference, but what the heck. Trying new things is fun.

Thanks for the advice.