I see your point on the rear tires. I'm not sure it makes as much of a difference as the front wheel weigh, but it definately should be concidered, if for no other reason as for extra weight.
Since the tires weigh more than I thought and most of that weigh will be concetrated on the out edge of the tire. They would have more of an effect than I thought. Which makes going to a larger diameter wheel even worse you put even more weigh on the outside of the axis of rotation. The difference in the weight between the tires isn't as great but the whole tire weighs more than I thought so it has a bigger influence. Plus with the thinner sidewall, the weight really is at the very edge.
I'd like to see a test done compairing same size rims and wider tires to see what effect this would have. I'd love to play with this at the track... too bad I don't have the money to go and buy a bunch of rims and tires and test the theory. Well we'll just have to settle for discussing it.

"To strive to seek to find... and not to yield."
Michael J. Kulaga
Michael_97RS@2gntDSM.zzn.com
aol IM: MJKulga