by TrackSmart on Thu Dec 22, 2022 12:03 am
This thread is a good idea. While blow offs are rare, understanding if some tire and rim combinations are problematic is pretty important. Manufacturers can't test every combination. Of course, even within a given model of tire and rim there will be variation. In my case, I had successfully used the same model tire on the same rim for a few years and over several thousand miles (i.e. 3 or 4 rear tires of the same model in that time period), so it was a solid combination prior to this experience. I'm going get this thread started again with my own entry.
Tire Brand: Panaracer Gravel King TLC 38mm (i.e. the slick/smooth version without additional armoring)
Tire Size: 38mm
Wheel Model: Light Bicycle AR24 (name of the rim, you can customize with different hubs/spokes)
Rim/Disc Brake: Disc
Hooked/Hookless: Hookless
Sealant: Stans
Rim Tape: 2 layers of Stan's yellow tape
Pressure: ~38 PSI at the start of the ride
System Weight (Rider+Bike): 170 lbs (145 lbs rider, ~19 lbs bike, ~6 lbs water bottles, clothes, and gear)
Tire wear: ~800km/500 miles (I usually burn through rear tires in about 1000 - 1200 miles and there was lots of tread left on this tire).
Blowout Date: July 30, 2022
Indoors/Outdoors?: Outdoors
Est. Ambient Temp: 85 F/30C
Blowout details: Started descending a paved hill. Tire blew out on the first curve in the road (thankfully, I had not yet gotten up to high speeds!). There was a sudden bang and loss of pressure. I was able to slow down, while riding on the rim + deflated tire. When I came to a stop, I saw that one side of the tire had completely blown off the rim. The tire was damaged -- it was no longer round and would not hold air tubeless. I installed a tube, noticed the tire had a bulge in it, and slowly rode it slowly for about 300 yards just to test it. It blew off the rim again with a bang!
My incident occurred during a gravel ride, but on a paved portion of the ride. I had used this same tire and wheel combination for at least several thousand miles prior to this blowoff. I had worn through 3 or 4 of this same model of tire on this particular rear wheel prior to the blowoff and had no prior incidents. It's possible that this particular tire was a looser fit. Or that I had lost some pressure just before the event, resulting in a burp on that corner, which precipitated the blowoff. It's difficult to know for sure, but I do not remember the tire feeling soft prior to the "bang". And I didn't notice any debris in the road or anything stuck in the tire itself after inspecting it. I'm grateful the blowoff occurred before I had gotten up to really high speed! This was the start of a long, steep descent that would have gotten me up to at least 40 MPH with a little bit more time.
Pictures (if possible):
