I have a few questions to ask you fellas....I just acquired an old 90's Cobra mountain bike from my dad last night after our talk about me wanting to build a motorized mountain bike. However I am about to buy an engine kit but before I do I need to know some stuff first and I dont quite know how to word it to find it in google....first question.....I have no idea how many speeds this mountain bike is.... Do I have to have it in a certain gear when I install the engine? Can I shift my mountain bike (w/o a jackshaft kit) while I have the engine on goin down the road? Should I have the rear sprockets removed and get a bike rim that is a single speed if I do not plan on buying a jackshaft kit? I am looking to do the easiest and cheapest build possible for myself...can someone tell me maybe an easy way (if there is one) on how to keep my rear gears (even if I dont plan on using them) and still have an engine...it confuses me on how this should be done...and how do I configure my gear ratio? Im new to all this and I am quite uneducated on all this as im sure you can tell so please bare with me.