I got my new Kenda Carbide-tipped front studded tire on (no, not that Carbide) and ready for a nice snow/ice ride tomorrow. I aired up the tires outside when it was really cold. Later on in the evening I decided to bring the bike inside to let the hub and bottom bracket grease warm up. Riding in the cold, cold morning can be quite a stiff experience even without having to get the bike parts to thaw out.
About 5 minutes after I brought in the bike - KER BLAM! The front tire blew out with a loud pop.
I inspected that this wasn't an issue with a pinch or studs poking through so I figured it was the temperature change. But having been through this before in the Texas heat and bikes in cars with exploding tires I had to figure out how much perssure change there actually was. So I found Guy-Lussac’s Law explained pretty well by Fix Werx and they suggest that you get about 2 psi pressure change for every 10 degress F of temperature change.
My case:
T1 = 24.8 F
T2 = 72.5 F
Add 460 to T1 and T2 for absolute temperature change and you get:
60/484.8 = P2 / 523.5
.12376 = P2 / 532.5
P2 equals 65 PSI. So only about +5 psi change for brining my bike inside for a tire rated from 50 - 75 PSI. However, in the Texas heat if you are running 120 psi and put your bike in the car you can really see how you could blow out a tire.
So I figure I attribute it to old tubes, lots of riding and really crappy rim tape that the manufacturers always put on stock bikes.
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