depends on how serious you want to get. for the fronts it's not a huge deal, you can run a smaller stud (they range from 3/8 to 1 1/2 inch lengths) i think i used a bag of 1/2" studs for my front, but for the rear, we use 1" or 1 1/4" 0studs and line the inside of the tire with either an old cut up street bike tire, or an old fire hose, or whatever we find :lol: The smaller studs you can screw right into the lug and not worry about it going into your tube. but with more power and the harder you ride, it will either fling the studs out of some of the lugs, or tear the lugs right off. the reason for a longer stud with a liner is the stud goes all the way through the tire and into the liner and therefore has a better grip in the tire and is not likely to fly out at all :1syellow1