Paul, I'm not your mom or your den mother, but I'm gonna encourage care.

Grooving up rubber for the trail is fair game (sweet score for a Benjamin!), but exercise some care with running that rubber on the street. In some states, it is illegal to groove tires not specifically stamped for that, and in most states, grooving out the wear bars is fully illegal. Whether anyone is actually looking for these violations is a whole different issue, but mothers, den mothers, and busloads full of nuns across America beg your consideration.

Sell me some cookies! :p

Randii