Infinity bike adapter

A simple adapter to allow converting an S2 base to an S4 base for bikes for infinity (and to allow for more visual dismounting).

narrow and wide fits are provided for the normal and newer style bases (with the sticking out arc markers), and it is inset so they will be flush to the top. It is hollow underneath for fitting magnets or counterweights.

Also included is the openscad file so you can tune it to custom bases.

Print with supports, and probably ironing unless you are going to be texturing the top, but otherwise standard.