I'm trying my hand at converting a McCullough 38cc. It look pretty doable, but I don't like the crank bearings. It looks like they are not made to take a thrust load--see picture. Also there are no keepers to keep the bearing from being pushed out, I guess when you squeeze the crank halfs together, the bearing cannot move?

I'm thinking about buying a bearing that can take a thrust load, anyone else have experience with this motor?

Thanks!