I actually designed the bike with a 1930's theme and is very highly customized, infact only about 10% of that bike came out of the kit I would also suggest getting your engine at custommotoredbicycles.com and you can also contact
that is if you don't live in California as they won't ship a 69/80cc engine and the little 48cc really don't have a lot of power, Don't! just buy a cheap engine or get the cheapest engine deal
"Good bikes aren't cheap and cheap bikes aren't good"
if you pm ME (private message) I'll give you Lynn's ph# and you can talk with her to see what would fit your needs, she is pretty square