tyre pressure?

[uk elephant]

BF just got me a floor pump with a pressure guage for my birthday. So I thought I'd check the tyres and pump them up to full pressure. I looked at the tyres and the rear tyre said max pressure 85psi, the front said max 75-100psi. So I pumped the tyres up to 75psi and headed off. Only got a couple of meters down the road and there was a loud pop under my bum. Turns out the rear tube exploded. So I walked home again. Tyre looks fine, but tube is busted. Now my question is, what pressure should my tyres be at? I'm on a Specialized tri-cross sport, but can't remember what the tyres are. The front is the one that came with the bike, the rear (where the tube blew out) is something from Continental. Not road bike tyres, a little wider and more tread. More like a hybrid bike I suppose.

[sundial]

I usually inflate to 5-10 lbs less than the maximum. That way when the tube expands, it shouldn't burst.

[uk elephant]

I thought that's what I had done. The tyre said 85psi max, and I only pumped it up to 75. Hm....maybe the tube has a different max than the tyre?

[Kalidurga]

Is it possible that your tube was pinched and just wasn't inflated enough before this to explode?

I've got Continental CityRides on my Tri-Cross and I usually pump them up between 70-80psi, depending on where I'm going to ride.

[uk elephant]

Could be. I'll check again when BF helps me get the old tube out. I guess I have always been on under-inflated tyres. I've only ever had a hand pump without a guage and pump until it seems full'ish. Seems the more I learn about cycling the more I realize I don't know.

[Blueberry]

I usually ride mine at max inflation, without problems (crosses fingers and knocks on wood). A pinch is certainly possible as Kalidurga suggested - also could be possible that your rim tape is starting to slip. If so, your spoke holes could have caused it when you hit a higher pressure. Can you tell where the tube blew??

Oh, and Happy Birthday!!!!!!!

CA

[uk elephant]

The tube blew a hole about half a metre long around the valve. Could have been pinched I suppose. I'll check the tape too just in case. Thank you!

[Eden]

Sounds like it may have just been a faulty tube - pumping it up to a higher pressure made it finally go. It could also be a burr or sharp spot around the hole in the rim that the valve stem comes through. Check that if it happens again.