hello everyone, i've been a long time lover of anything with a motor on it. about 2 years ago i built my son a mountain bike with a 31/2 horse vertical shaft lawnmower motor. i posted awalk around explanation video,a video of my son riding it, and several pictures. as i was checking out this site a little while ago i came across a referance to my myspace site where its all posted. i invite anyone to check it out and comment please. i would also like to asure anyone who wants to atempt to build one that it works quite well and that i have built several for family and friends. we have replaced one tire on the rear of my sons bike so far. when the original started to show a little wear on the sidewall we turned the tire around and then replaced it when it started to wear on that side. [10 bucks at k-mart]. if any one has questions please e-mail me and i will try to help.