I think I found the perfect kit!
http://www.amazon.com/Scooter-Bore-7...m+big+bore+kit
Mainly because it comes with a performance camshaft. Unless somebody else has some opinions by the time I order it, around the first weekend of next month.
I'm really tempted to get that 50mm bbk, but I read horror stories of people breaking things with so much power, and even though 72cc isn't much of an upgrade from 63cc I think it will give me just enough umph to reach my goal of 45mph. Plus I won't have to change anything with my carburetor other than maybe the main jet, I think.
Unless I find some preventative measure I can take to increase the longevity of my engine with a bigger bbk I think I'm going to get this one... I sure hope the performance exhaust will work with such a meager bbk, haha.