He has a 48 V battery so does have 1050 W on tap. A 36 V Q128C wheel would get down the road pretty smartly with that controller and battery if they are compatible.
Depends on the cells inside but if they are 6P then even average crappier 4 - 5a cells would be ok for a couple of years.
Boardman cx/mx (1) Oxydrive kit(270rpm ). (2) Bafang cst & KT kit (270rpm), (3) Q128C & KT kit( 201 rpm)), (4) Yose CST & KT kit (270rpm).
