look of this combo?
#5
wheel
#7
Yea, you're getting kinda skinny for the tire. I've never seen that size mounted on a 20. IMO only, a 9" should be the minimum width for a 12.50, and a 10" preferred. But that's usually on a 15-16" wheel. May look OK on the 20". Don't know. I am however, only talking about looks, not performance. I think it would work just fine as long as you are happy with the looks. I don't think I would be.