Got some new bicycle tyres yesterday (CONTINENTAL COMFORT CONTACT 700 x 32c CITY COMMUTER ROAD) The tyre I fitted to rear wheel seems to have a bulge in sidewall. Took it off, looks ok inside. It feels perhaps a bit thinner where its bulging. The tube seems a bit big for the tyre but I doubt this could cause it?!? and the front is ok with same tube. Previous tyres were 35c.

The bulge is perhaps 10mm diameter and 1-2mm deep. Not very visible but immediately feel it if rotating the wheel.

They were from an ebay shop and arrived twisted / folded in half so as to be much smaller to post - wire bead type. They seem to spring back into normal shape when unpacking them, no visible damage. I assume the folding may have stretched/torn a cord?

Edit, I did remove, inspect, rotate and refit the tyre. The bulge was in the same part of the tyre, so its not the tube. I inflated to about 65psi. Recommended on the label is 70, max 85.

I did see the other post, but that is showing a used, damaged tyre, rather than a brand new one. Thanks I will be sending it back.

  • 1
    possible duplicate of Is it safe to ride on an unevenly bulging tyre?
    – Batman
    Commented Dec 7, 2014 at 14:26
  • Check if they are inflated to the correct pressure. Or try with a different inner tube. If possible send them back! They are not folding tyres anyway so folding them for transport caused some damage.
    – Carel
    Commented Dec 7, 2014 at 15:15
  • 1
    I would pull this tire and rotate it a bit to see if it just seated poorly. Most likely the tire is bad but I would give that one try.
    – paparazzo
    Commented Dec 7, 2014 at 17:37
  • Double-check that the tire is seated at the rim properly. If you look closely there will be 2-3 ridges in the tire sidewall, running in circles around the sides, near the rim, and, when the tire is properly seated, a given ridge will be a constant distance from the rim. If you see the ridge wavering in and out at the rim you need to depressurize and work the edge of the tire in or out to make it even. If that's not the problem then it sounds like you have a defective tire -- rare but not impossible. Commented Dec 7, 2014 at 23:00
  • Double check that the bead is not defective as well. I had a bulge on a tire (more along that it wasn't seated evenly) but found out later that the bead was separating. I got lucky, it caused small tube punctures before it ripped off.
    – BPugh
    Commented Dec 8, 2014 at 15:25

2 Answers 2


Something is wrong with the casing. Not safe to ride. Sometimes the come from the factory that way, who knows why. Send it back and get it exchanged. Don't risk a catastrophic blowout.


Consider buying unbent (wire bead) tires from a local bike store, not cheap, from ebay, imported from some country with no standards.

  • 1
    You have no knowledge that the eBay seller wasn’t in the OP’s country. Furthermore, the OP specified Continental tires, a well known brand. The issue of importing the tires from a factory with poor quality control isn’t at issue. The fact that the OP probably lacked a warranty (note the date of the post) from an eBay seller is a possible issue worth pointing out, but it doesn’t help the OP. In fact, the OP doesn’t seem active on Stack Exchange anymore.
    – Weiwen Ng
    Commented Sep 27, 2020 at 19:38
  • Continental are a German brand, and while their cheaper tyres are made in Thailand, they do make a good product. Folding bead tyres are also lighter than wire-bead tyres, which is always good for a bike.
    – Criggie
    Commented Sep 30, 2020 at 18:49
  • This doesn't answer the question. Commented Oct 2, 2020 at 2:44

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