Tyres Exploding Off Rim - GP 4 Seasons

angrynortherner

I've just fitted a set of GP4 Seasons to my Ksyrium SL's and have had two massive punctures as a result of the tyre bead bursting off the rim. The front doesn't have these problems, only the rear and the tyre was inflated to 120psi the first time and 110 psi the second. The tyres seem to blow after steep hills (could the tyre be rotating and removing the bead seal?) with the most recent happening at a junction after a short but steep climb.

Has anyone had a similar problem with a Ksyrium/Continental combo? Could it just be a duff tyre?

sylvanus

The only time I've ever seen this was when the tube was 'pinched' by the bead. Are doing the partial inflation then knead the bead round the rim thing? Makes sure the tube is properly sat and not pinched.

It could be a duff tyre but I doubt it. Have you checked the rim is ok and not bent / dented?

angrynortherner

The rim looks fine, it's only got around 180 miles on it I have checked the bead but maybe I've just been unlucky. Will try what your suggest and keep an eye on it, otherwise it's going in the bin.

romans

Have used these tyres for years on Alex and Mavic rims with no problem (which means have not got through many tyres). How about changing the front and rear over? Have you put in new tubes? I built up a set of wheels recently and used new tubes I had bought cheaply without looking at them. Two tubes blew rapidly just by hitting a small stone without piercing or rimming the tyre and a repair patch would not even stick to the tube. Looking at the tube it was made in China and the rubber colour was grey not black. Now using only good tubes.

Romans

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