I just got 2 new Panaracer Gravelking SK tires and mounted them tubeless on WTB i21 rims with the correct width rim tape from WTB. I inflated them to 60psi to set the bead and the rear blew off the rim before even taking it off the stand.
The rim is now way out of true. In fact, I think it has to be replaced now.
After this happened, I trued the rear wheel as best as I could and re-installed the rear at about 40psi. I went for a test ride and 2 minutes in, the front blows! It was between 50-60psi at the time. And now the front wheel is severely out of true as well.
- Is that normal for a rim to be ruined from a blowout?
I realize that I should not have inflated them to their max rated psi (60psi max for tubeless and 75psi for tubes). But, in my experience, I have never had a tire blow out right at the max psi. Most tires can go way beyond that for a short period, especially for just setting the bead.
Is this rim/tire combo just incompatible?
Should I just run tubes with this combo? (I have trust issues now).
Ok, so 60 psi is a little insane to ride on for a gravel tire. I get that now. I talked with WTB about this and they see no reason the tire should have blown off. They did give me crash replacement pricing for new rims. I have since rebuilt the rear wheel with the new rim and I am now running the same tires on the old front wheel and the new rear wheel. I will be rebuilding the front wheel soon, once some more parts arrive. I have been running this setup for about a month now at 35-40 psi with absolutely no issues.
Here is my theory of what happened. I think my floor pump gauge was starting to fail when I originally pumped up the tires and it was reading much lower psi than it actually was. I think this because just recently, the gauge completely failed and reads all over the place. Who knows how high I actually pumped them up to when they blew.
Just an update on where we are at with this. After rebuilding the wheels with new WTB i21 rims, I have now run this rim/tire combination with zero issues for over 2800 miles. I have had to re-seat the tires a handful of times as well. I have been consistently running 35-42 psi. I don't plan on going any higher due to trust issues. However as a recent answer mention, it's possible the older rims were build out of spec. Unfortunately, I don't know how old they were, but they were the exact same make/model.
Side note: Gravelkings wear very well and I haven't had a single puncture that I am aware of! After 2800+ miles, I probably have another 500-1000 miles left.