Just another newbie in need of assistance.

[magnumluver]

Hi, i'm just another newbie to join this great forum. I recently purchased a w.c.c. jesse james chopper bike and my 80/66 cc kit from zoombikes is on the way. I plan on bringing the bike to a machinist to get the engine mounted to the frame but I would like to do a fair amount of work on my own. i'm wondering what I would have to do to turn that faux-gas tank into a real one? Also, since the wheels are only 20" I know i'm going to need to get a new sprocket, should I get a 36t or smaller? Where can I get smaller sprocket than 36t? I have plans on putting the front disk brake from my old norco on the front wheel, what kind of work would that involve? sorry for the absence of pictures but I'm sure the most part of you know what it looks like( or you could just google jesse james chopper bicycle.)

Thanks for all the help guys!