I’ve got an old CT90 that has been in the family since long before I was born, and I’d kinda like to build it up into a restomod commuter bike. I want to keep the looks as close to stock as possible, but need some more power to cart my 200# butt up to say, 55mph without too much difficulty. The bike has a good bottom end but the top end is completely junk, sat outside for 10+ years with spark plug missing, piston rusted to the bore, valves are pretty much destroyed. My thoughts are this, Is it possible to get a bigger cylinder and head, that will work on the stock Honda 90 bottom end? Is the bore the only thing different between an old 90 vs newer ‘Lifan’ or what have you 125, 150, or even 160cc? I’ve found piston and cylinder kits for 150cc Lifan engines, as well as new assembled heads, what else might I need to make this work? New cam? Cam chain? Gaskets to fit the big bore top end? Thanks!