I'm new to this forum but not exactly new to the hobby. My minibike is what mainly got me into small engines and bikes, it's a 1970 Rupp with a 5hp Briggs. Ive only had one motorized bicycle and it used a 25cc homelite engine that had a craftsman socket spindle for friction drive. it was a pain to keep running right (mainly because everything on it was rigged to work)but fun to ride when it did. After a while though it got irritating and I took it apart. my current project right now is a motorized bicycle that ISNT going to be rigged together, using a 99cc Predator engine I scored from eBay.. ill start a project log right after I post this.