Hey – i recently had a tubeless tire sidewall blow out. My main concern is this is the second time this has happened and I'm wondering if its me rather than another faulty tyre.
The first one happened gradually but this time it exploded / gunshot and running on rim in 0.5 seconds. I was going about 10km/h uphill thankfully, but it would not be ideal flying downhill in a curly situation.
- Pics of recent one attached
- This was on rear wheel, i think the other was the same but not sure
- Both were maxxis gravel tyres, one was a rambler, this one a re-fuse
- I installed 'normally', by hand, no levers
- I have Hunt adventure 650 wheels, checked the rims and nothing out of sorts.
- Was running it at about 50psi, so a little high but within manufacturer tolerances
- Its a sort of heavy set up, steel gravel, 1x pannier, i'm 80kg, but i assume still within manufacturer allowances (you would hope!)
- Generally I'm commuting, a little gravel, I push the bike a bit e.g., the odd gutter drop (not hop), take the bumpy path but its still mostly paved riding. I thought a gravel wide tyre set up should handle this.
There is an indent on the bead at one end of the damage. I can't imagine I did that to it before it happened, but possibly. At a guess, it more likely happened when the blow-out occurred. A possibility was it was damaged when it was folded / shipped, they do squeeze them up…
I've been considering going back to tubes for a variety of reasons and this might push me over the edge.
Was this my fault? Any tips on how to avoid it in future?
Thanks!
by Dew_Disappears
7 Comments
Maximum pressure is a function of the rim AND tire. Not just what’s written on the tire.
What diameter and width is this tire? 50 PSI seems high for anything wider than maybe 38-40mm on a 700c.
If you exceed the pressure the rim can stand for a given width, blowing the tire off the rim will often result in damage like this.
Some cursory googling of the specs of the models of your tires and rims tells me your rims are hookless but your tires are hooked. Double check me on that.
If you confirm those specs, that’s definitely the cause. Hooked tires on hookless rims are incompatible and are a recipe for a blowout and results in this exact type of damage, because the tire is not provided with the rim structure it requires to remain seated.
Thank god you were not going down hill on either of these blowouts.
EDIT – Hunt Adventure carbon appear to be hookless, and Hunt Adventure aluminum appear to be hooked. So it would depend on the model you own. Rambler is not hookless compatible.
What’s your tire size and width? You can put the specs in here to get the right pressure.
https://silca.cc/pages/pro-tire-pressure-calculator
I bet you should be running closer to 30 psi.
Are you using carbon or alloy wheels? If running the alloy I wonder if the maxxis tires simply aren’t compatible. Look at the wear in the bead area to both sides of the blowout. It appears to show wear from what looks like rubbing.
Disc or rim?
50psi on gravel with tubeless? Why? I don’t even run my gravel tires that high on tarmac.
Maybe you have a sharp section of rim?
You can generally pump up tires +10psi beyond their rated pressures and it still shouldn’t be an issue, as it’s part of their engineered fudge factor.