Here's my old motorbike, built about 5 yrs ago. It was built up on a salvaged mt bike frame. It uses caliper brakes and I included a shot of the brake lever I used. It's made for handicaped folks but works very well to activate both front and rear brakes.
I added balloon tires,saddlebags (I made those) a big wide handle bar that looks like the ones from old motorcycles and a set of chrome fenders. The seat is from an old exercise bike. I recovered it (I'm an auto upholsterer by the way) Watch the trash for these. They turn up now and then and are very comfortable.
The headlight is homemade and runs from a 6 volt battery in the saddlebags. Same for the taillight.
On this bike it was better to use the idler with the kit on the peddle chain and the drive chain is direct. Enjoy and if you have questions , feel free to ask.