Yep, you will be fine. We have plenty of guys running that setup in our club that air down to below 10 psi sometimes and have absolutely no issues.

 

I have had 3.50 gears and 35s on an AX15 for years now. People exaggerate how "bad" it is. BUT...4.56 would be more enjoyable. No arguement there

Don't worry about the rim yet. I would say a majority of people on that tire size are on 8" rims. If you are losing beads on an 8" OR a 10" then it is time for beadlocks, IMO. It is not easy to lose the bead either way unless you are airing down too much...and again, that would be call for beadlocks

 

8" would be the min i would run a 12.50 on. 10" would be the max. either is good and will work fine.

 

8" rim for a 12.5, 9" - 10" for 13.50s works great. It is what I run and I've never have a problem airing down. The only bead I've lost on an 8" rim was a 32x9.50 15 TSL at 6 psi. on a side hill.

 

I have always thought that a smaller rim width was better for airing down.

 

It is!