Mine wasn't sticky yet but sure left a black grime on my hands just the old tractor steering wheels on the farm.
This is what I did:
I filed open slightly all the cracks in my wheel and cleaned them. Next, I sealed all the cracks with a heavy duty epoxy. I sanded it all smooth and then shot an industrial epoxy primer to seal it. Next, I painted it with a compatible industrial topcoat. It turned out great. Mind you, I haven't driven the truck with it yet.
Sanding that wheel was a dirty, long process.
https://photos.app.goo.gl/IZl1FJLM6TjLje3r2
