Midnight exploding tyre problem

GyatsoLa

Ok, I know there is probably a very simple explanation for what happened last night, I'm just not sure what it is....

I removed the rear wheel (Sun Mach IV, 559-22) from my Kona singlespeed to replace both tube and tyre (nozzle thing snapped on the tube, tyre has been on the bike for several years and several thousand km). The tyre is a Tioga Red Phoenix 1.90 (a very light racy piece of rubber) - its the original tyre on the bike, about 4 years old. I was surprised to see that the tyre was in pretty good condition despite its miles, so decided to keep it (also realised that my replacement tyre was too wide so I couldn't use it anyway).

I replaced the tyre and tube and pumped up with my Joe Blow track pump. I noticed a very significant bulge on the tyre around the valve area - so much that the rim of the tyre was visible. I deflated and checked to see if the tube was in correctly - it was, no twists or anything like that.

I reflated and the bulge was less prominent, but still there. I inflated to 45psi (although it felt harder to the touch so I'm not sure the pump indicator is exactly right) and decided to leave it until the next day to see if the bulge was still a problem.

While asleep last night I was awoken by what I thought was a backfiring car....

When i got up this morning, there on my kitchen floor was the bike, with the rear wheel deflated, part of the tyre blown off the rim where the bulge was. Didn't have time to remove to see what sort of damage there was inside.

So what did I do wrong? Maybe my tube is too big? I've read reviews that say its notoriously difficult to change the tyre on a Mach IV, could it be that the tyre just isn't hooking right inside?

.blitz

If there's a bulge in the tyre it means the carcass has ruptured or even worse the bead has broken.

This happened to one of my son's mates as he was trying to blow up his knackered BMX tyre to 100 psi using my pump. It exploded at about 80 psi, you should have heard it go off

nicklouse

damaged bead, or incorrectly seated bead.
not much else it can be.

GyatsoLa

okie doke, I thought it might be something like that.

New tyre it is then. I guess I should be relieved its not new eardrums I need....

dave_hill

GyatsoLa wrote:

I guess I should be relieved its not new eardrums I need....

Or even new eyes.

I knew someone who had a motorbike tyre explode off the rim whilst inflating it with an airline. It was a brand new tyre but the sidewall must have been defective. The bead tore off the tyre, whipping matey across the face and effectively removing his right eye.

downhillholty

ouch!! :roll:

Gingersaurus

I've had a couple blow up in my face. They were on about 90psi too. Couldn't hear for ages after.