as the first post asked what do you weigh? i ride the williams system 30s now as my everyday training wheels and they do great. they are plenty stiff and roll extremely well. the only down side is the weight. if i had it to do over i would have likely bought the boyd wheels due to that fact they are lighter but im not disappointed that i didnt. either way you go i think you will be happy. call keith williams if you have any questions he is a great guy to deal with.