Buggered if I know

[PINT of Stella, mate!]

Alright folks?

After a relatively event free, -hell, somewhat decent plane trip (No excess baggage charges, good films on the flight, booze) I'm finally back in sunny west africa only this time I've taken along one of my bikes for scooting around camp on (theres loads of jungle and some pretty steep hills so it should be cool...)

Anyway I'm digressing a bit. I assembled the bike as soon as I arrived and had been pissing around on it for a couple of days when I decided to swap the tyres around. After changing them out and pumping the tubes up I left the bike leaning against the wall in our office. About fifteen minutes later theres was a really loud bang. The front tube had exploded pushing the tyre off the rim! (It scared the shit out of half the office staff as well, I think they thought the local rebels had kicked off again!)

Now I'm absolutely scoobied as to how this could of happened. I'd pumped it up with a small hand pump so it's unlikely I exceeded the max psi. The office is air conditioned so heat probably wouldn't be a factor nor was there any major changes in pressure. The bike hadn't been moved either.

Basically I'm stumped!

Has this ever happened to anyone before? Or has anybody got any theories?
If it was a preventable problem, please let me know as I'm out of spare inner tubes and bike shops are pretty rare in this part of the world!

cheers

[johnny]

How long had you been using that tube for previously?

What bike are you on?

[roxy12]

happened to me once, but it turned out the bead in the tyre had bured through the rubber and just popped the tube.

soudns rather odd, any chance anyting may have been disloged inside it?

[Binaural]

It's happened to me before with lightweight XC tyres - you pump the tyre up with part of the tyre bead unseated. Takes a while before it blows sometimes, and surprisingly easy to miss while pumping up the tyres as well. It can blow up when you're right next to it as well, which will scare the shit out of you!

[demo man]

that's actually kinda funny!

i can't help you with that one at all, but I'll tell you what mate, if you need a spare tube that badly PM me your address and tube specs and I'll send one over.



hehe, i bet the office staff shat themselves.

[S.]

It's happened to me before with lightweight XC tyres - you pump the tyre up with part of the tyre bead unseated. Takes a while before it blows sometimes, and surprisingly easy to miss while pumping up the tyres as well. It can blow up when you're right next to it as well, which will scare the shit out of you!

Yeah I'd say that's almost certainly the case. The tube will slowly push the bead over the edge of the rim, then once it's pushed it far enough to be able to expand between the tyre and the rim, it'll explode. Scares the living turds out of you when it happens WHILE you're pumping a tyre up (and on cheap kids' bikes and whatnot, it can actually buckle the wheels quite badly too).

[PINT of Stella, mate!]

It would have been a fairly old tube (maybe a year?) so that may have been a factor. I initially thought it may have been contaminated by chemicals on my hands, but we'd not been using any that day.

I obviously let the air down in the tubes before the flight but they weren't completely empty so maybe that might have helped cause it?

Oh, the bikes an '04 Kona Caldera (XC hardtail)

[PINT of Stella, mate!]

Cheers lads, for the answers. I'll definitely check the bead next time I change a tyre - I'm screwed if I don't!

Thanks for the offer Demo man but we have enough trouble trying to get work equipment into the country! I'll back on my leave before any post gets anywhere near Angola...

[Dicky]

I once had a case where Dad asked to borrow the shop pump... while kiddo was still in the stroller... poor little fella

[and1]

Couldve been the tube wasn't seated properly and with the inflation pinched against the rim, or the thread on your tyre was burred and pressed on the tube and caused a puncture, or maybe some terrorists used mind power to destroy it!!! Anyway, no biggie, spend a couple bucks on a new tyre and your all sweet my non Australian resident friend.

[nik_1974]

Couldve been the tube wasn't seated properly and with the inflation pinched against the rim
Yeah this has happened to me with new tyre and tube. Rode the bike for about a km into the bush and BANG:eek: no spare tube or anything. The tyre also came off the rim as well. Just make sure your tyre is seated properly and the tube is in right.

[scratchy]

What's the TPI of the tyres? Tyres with a low TPI (Thread per inch) have a tendancy to "grow" if left at high pressure for a period (or low pressure at high altitude- say in a plane. Are the tyres very easy to get on and off with your hands or do you need tyre levers? I had some specialized Enduros that I couldn't store at running pressure otherwise they would rub the chainstays.

I can't believe you didn't take more tubes.

[PINT of Stella, mate!]

I can't believe you didn't take more tubes.

Yeah, but I was trying to keep my baggage weight below 20 kg (every little helps) and I figured 1 spare tube and a couple of small puncture repair kits in my carry on luggage would be sufficient for this trip. I reckon I'll still be alright. Might just have to avoid the perimeter of the camp for the time being (it's landmined...)

[johnny]

Can't you mail order some?

Say hello to the Saro-Wira family for me ;)

[Binaural]

Yeah, but I was trying to keep my baggage weight below 20 kg (every little helps) and I figured 1 spare tube and a couple of small puncture repair kits in my carry on luggage would be sufficient for this trip. I reckon I'll still be alright. Might just have to avoid the perimeter of the camp for the time being (it's landmined...)

Landmines? Time your approach right and you should be able to air it over the perimeter fence and on to freedom!

[scratchy]

Yeah, but I was trying to keep my baggage weight below 20 kg (every little helps) and I figured 1 spare tube and a couple of small puncture repair kits in my carry on luggage would be sufficient for this trip. I reckon I'll still be alright. Might just have to avoid the perimeter of the camp for the time being (it's landmined...)

Makes sense to me. Different tyres and rims have slightly different fits, yours must have been a loose fit. Maybe try a different brand tyres, if you think you might need tyre levers to get it on, that's probably a good sign. Also don't store the tyres with normall pressure in them. Keep say 15psi in them to prevent them stretching.

[Oddjob]

Yeah, but I was trying to keep my baggage weight below 20 kg (every little helps) and I figured 1 spare tube and a couple of small puncture repair kits in my carry on luggage would be sufficient for this trip. I reckon I'll still be alright. Might just have to avoid the perimeter of the camp for the time being (it's landmined...)

You need to make friends with the diplomatoic staff at one of the embassies. They don't weigh diplomatic pouches and its quicker than the post to your part of the world.