I figured it out in the middle of a driving class (about 11:15, EST) but I didn't have internet access when I got it. I was double counting the tau/r which led to the erroneous assumption about the direction of friction I had before. The friction is what drives the wheel forward, not tau/r.
I got the right answer all by myself, though, after I figured that bit out. I learned a little physics, too.
