i blew a main seal in my trans mission, which cost me a pretty penny to fix. Also, BE ABSOLUTELY SURE THE EXAUHST IS NOT LEAKING!!!!! otherwise the moped will run rough at top speeds, and you wont get the maxiumum performance out of it. I have the 27 tooth sprocket on mine right not, and can get the needle to back around to zero. i know that shifting often takes a second or two with tomos mopeds, and with the bore kit, it shifts in about half a second. I lost the aiffilter to my amal carb. I put a valve cover airfilter from pepboys on my carb instead, which provided better flow, but it did get in the way of the peddles, so i could peddle it, only kick it back to start it. However, it does look really cool. ill try to get pics of it. If you go to pep boys, they should have it, but youll have to enlarge the hole to fit it on the carb. i sincerely think that the performance i get from the kit is worth the little problems!