Originally Posted by NoRacer
If that is a Mavic CXP33, then the widest tire to be placed on that rim, according to Mavic, should be 28mm @ 117 psi max. OP, did you say that you had a 37mm wide tire on that rim? I see that WTB has the Slickasaurus in 28mm, 35mm, and 37mm widths.
This may be on the right track.
I had an ancient MTB rim that was run with old brake pads for a little too long, so the braking surface was weakened (which I didn't know at the time). I moved the wheel to my kid/trailer/trail-a-bike hauling rig, and put slicks on it at much higher pressure.
On the first ride, the rim walls separated at the seam and released the tire, so the tube exploded. The rim was bent blown out about 1/4 inch right at the seam.
I think tire pressure over a larger area could be to blame here. It's not the same failure mode as mine, but the tire overpowered the rim, which sounds similar.