Well, I have been doing a bunch of research and it looks like I would have to buy the 120mm HD Bafang to fit my fat bike and clear the chain stay. It's the 1000 Kw and then after pricing all of the special tools, I will probably need, I am within $500 or so of just buying a new Rad rover so I don't know, And then it looks like you still need to program the Bafang to make it more user friendly and I am not much on computers. I am going to test ride a Rad rover and if I like it, for 500 more and I still have my old bike to ride, also, the Rad just may be the way to go for my first Ebike.