Originally Posted by old motorbike
I do ride my 1400cc motorcycle that will do over 200mph, but was missing some fun with a homebuilt motorized bicycle. The slow result of the 49-52cc motors has me yearning also for a 125 or so dirtbike engine and trans for a bicycle. 40-60mph desired.
I too have owned numerous motorcycles and just like you I would like more power. The part that everyone seems to forget is that when you upgrade the motor you have to upgrade the rest of the bike as well.
By the time you get to something in the 125cc range you might as well just purchase a 125cc sportbike. It will be cheaper and safer. It was designed to handle the power.