Repeatedly burst tyre at rim

andy2307 Posts: 2
edited February 2013 in Workshop
I have a fairly old custom road bike with 700c wheels. I had a blowout on the front tyre, where the actual blowout was roughly level with where the rim touches the tyre. I bought a new tyre and the same problem happened again. To enable me to get around before buying another I put on an old spare tyre, this also blewout in the same location and the tyre was heavily scored (mainly on one side) where the tyre meets the rim. I can't notice any sharp bits/anything unusual with the rim. Does anyone have any suggestions as to what could be the problem or have they experienced the same problem?


  • Definitely check that the brake block is nowhere near catching the tyre. I've had that before blowout the sidewall not right on the rim though.
  • sungod
    sungod Posts: 16,853
    ^^^ this

    if the brake block is too high in the holder (or the wheel not fully seated in the dropouts) it will damage the tyre

    look at the brake block from the front, if this is the cause it would probably have a protruding 'step' on the upper edge
    my bike - faster than god's and twice as shiny
  • John.T
    John.T Posts: 3,698
    Also take the tyre off and check the inside of the rim where the tyre sits. If this is at all rough it will chafe through the tyre. Just smooth it down with fine emery cloth or similar.