This example just reinforces what I've been saying. Here is Yamaha selling a bike about the same size/weight and similar size engine as an XS650. Do they choose a narrow tire for the rear to get that superior handling that some of you suggest. No, their engineers chose to use the same size rear tire that my XS650 Special uses. Its obvious they prefer that width of tire on the back. Note also that they use a 16" tire, not an 18" tire as used on the XS650 Standard. I think Yamaha engineers knew a thing or two about wheels and tires, and its shows by the size of rear tire they chose.