Honda Spree and Elite 50 Forums

So if I could score the blue one with that sa50 engine on it, if the engine is good, I could transplant that on my 87 aero? Sorry, this is all new to me.

You need to read up on engine swaps and what's involved. Only another 1987 SE50 engine will be a direct swap-in. The SA50 engine will fit, but will likely require rework of engine mount (read: welding) and probably some other minor items.

You can find a costly crank here : https://www.cmsnl.com/honda-nb50m-1985- ... 6_1HdczbIV
Or only the part you need (left hand side of the crank) and have a shop do the replacement job. It will still cost $$$