Just saw your question regarding the spocket. The rear brake drum is from Worksman Industrial Bikes. The brake shoes are about an inch wide, the rest of the drum is hollow. I just drilled and taped the bolt holes in the flat of the drum side and kept the bolts long enough to put on a nylon lock nut on the inside for extra insurance. if you note the rim is opposite of a bicycle (right hand chain) I mounted the rim on backwards to line up with the drive on the motor. I didn't want to add any more width to the right side of the bike because it has a kickstarter. Thanks!