Only just my Opinion! This is an exceedingly bad idea. These are expensive potentially dangerous engines that produce more vibration in the plane of rotation than small engines. Anything attached to that crankshaft needs to be up to the job and not cheezy, cheap plastic. Think about it why would many use multi bolt hubs instead of the common single nutted shaft\s with small engines? Also if you are going to use a capable electric starter plastic spinner is even a worse idea.

John