I pulled off from a stop sign today, got rolling good and nailed it, expecting to lift the front tire a few inches and carry it for a little way. Instead, the rear tire started hopping rather violently. Hard enough that the seat hit my arse enough to make it hurt. I kept it nailed and shifted to second and it hopped about twice more. I've never had this happen on a bike before, but have felt it quite often back when I used to drag race cars. I suspect that it may be because of the big darkside rubber on the rear. Anybody else ever felt this?