Dangerous tube blow outs - DA 7850 50mm Carbons

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Re: Dangerous tube blow outs - DA 7850 50mm Carbons

Postby fixie » Thu Mar 18, 2010 9:09 pm

twizzle wrote:
To quote Jobst Brandt :
The high temperature blow-off seems to be a combination of effects
that include primarily increased pressure from heating and the
softening and slipperiness of the tire bead that heat causes. In any
case, enough tandem riders have overheated tires that exploded off the
rim, that it is a known phenomenon. Because we don't know the
temperature of the air in the tire that exploded, we can't make an
estimate of the pressure. One thing is certain from my experience and
measurements I have made, is that the rim gets hotter than 120 deg C
and that steam can be generated from water inside a hollow rim. I
don't know how hot a tandem rim gets.

I think that this link has some helpful if somewhat anecdotal information.
Thank you Twizzle
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by BNA » Fri Mar 19, 2010 6:46 pm


Re: Dangerous tube blow outs - DA 7850 50mm Carbons

Postby oldplodder » Fri Mar 19, 2010 6:46 pm

My experience suggests from the photos that the tyres are too loose on the rims. When the loose tyres are fully inflated the clincher effect is diminished and the tube can work its way between the tyre bead and rim. The tube is thin when inflated. If it is not contained by the tyre and rim the wall becomes very much thinner and will fit through a tiny gap (ala bubble gum). Try different tyres, and good luck in solving this issue.
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"Cycling is for life"
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Re: Dangerous tube blow outs - DA 7850 50mm Carbons

Postby Ross » Sat Mar 20, 2010 5:32 am

What sort (brand/model) of tubes are you using? I had some problems with exploding Conti Race Light tubes a while back, gone back to using regular Conti Race 28 tubes and no more probs. Luckily my blowouts occured while the bike was stationery and not while I was riding. My wheels are Mavic Kysyrium ES not DA carbon though.
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Re: Dangerous tube blow outs - DA 7850 50mm Carbons

Postby Evo6point5 » Sat Jan 26, 2013 10:13 pm

Thread revival.. Only because I had a brand new gp4000s explode on me today, ruining my tri.

Never had this happen to me in my life until today and just seems weird that there are so many threads about gp4000s doing this. Everyone looks for reasons but I've fitted hundreds of Tyres and not once has a tyre ever exploded.

Didn't come off the rim but has burst a split in the side of the tyre.

Can't believe there are so many stories about this now that I search. Won't be using these pieces of crap again. Luckily it burst 300m after a short 60kmh+ drop or could have been nasty.
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