The rear rims are not 12" wide, Austen. They are actually 10-1/2" wide. It's the tire width that is ~12" wide.
It just so happens that I just bought (and received) a pair of these rims from a forum member for those 26.5"x14-12 Carlisle Ultra Trac tires that I bought back in May. The standard 10-1/2" wide rims are recommended for them, as well. Lucky for you that I haven't mounted the tires on them yet.
Here are some pics I just snapped of the rims.
Wow!! I stand corrected. I would have never thought that seeing as how none of mine have any buldge on the sidewall?
Learn something new everyday I guess. I'm stumped more than anything now?
Edited by stiemmy, November 06, 2016 - 11:23 AM.