I have to admit the 160/60/17 handles better than the 170/60/17. Just so you know, the first number denotes the width of the tire in MM. The second number is the aspect ration (Height to Width), and the third is the rim diameter.

A wider tire with the same aspect ratio (the '60') will be slightly taller too. Therefore your speedo will lose some accuracy. About 2% if you go from 160 to 170.

 

first off.. I couldn't figure out a word of what CBRFEEK is talking about. Second, you will not lose speedo accuracy, depending on the bike.. if your bike has a front tire driven speedo, you can do whatever you want to the rear tire, gearing, etc with no change in speedo calibration

third, I have an 88 hurricane 1000, and my bike didn't like high lean angles on high speed corners, it had a metzler on it, very squared... I put a new bridgestone battleaxe on it, properly sized for the bike, and the bike handles WAY better.. it you really want a bigger back tire, get a differant swingarm, rim and tire...

also remember, that if you have a bigger contact patch, it's more tire that needs to warm up.. and more distance between the center of the tire (straight riding) and full lean, where you *really* need traction.. so the tire may not be as sticky on the sides when you go into a corner after riding straight a while.. Just a thought