Originally Posted by noisebeam
But I wonder if wear patches are only caused by skidding? Since I accererate... doesn't this wear the tire out in patches too, although slower than skidding?
I think you're looking at wearing your tires down from acceleration in extremely small rates as opposed to skidding. Some of the people that really seem to be concerned with this stuff, like mikearena who wore through his $35 tubular in one parking garage skid, acceleration doesn't even have a chance to play a role in this.
As far as your other questtion, the rule of odd numbers is good advice. 49 is a great number also cause it's only divisible by 7. And 49 x 14 is just huge for the street. I ride 49x 15 right now, but 49 x 16 and 49 x 17 are only slightly better as far as patches go.
Correct me if I'm wrong, but isn't the rule about switching feet (skidding with your opposite forward) to double your skid patches only practical if you have an odd number of patches from the chart?