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I noticed starting yesterday my front tire has been making a strange sound. It sounds like there is a small piece of tar stuck to the front tire and it makes a faint noise of sticking and unsticking from the pavement once per revolution. I inspected the tire by hand, and it is perfectly clean. There is nothing visibly wrong with it whatsoever. It's also not melted. The bike rides perfectly. The tire and tube are both very new. The sound happens whether pedaling or coasting. Sometimes on different road surfaces it disappears, but I'm not sure.

Because the sound only happens when moving at speed with weight on the tire, I can't reproduce it standing still. Unless my ears are broken, it's not coming from anywhere else on the bike. What could this possibly be? Paranoid delusion?

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    Possibly something on the brake pad or brake track? Also, since it only happens with weight on the tire, might be spoke related, i.e. you have a spoke that is not tight or something and makes noise when loaded. (Kind of like a Saturday night date.)
    – JohnP
    Commented Aug 23, 2012 at 15:11
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    Yes, could be the brake pad brushing the rim, a loose/broken spoke, a bearing problem ... Or could be a defective tire, with a separation between tread and cord. With the wheel raised off the ground, spin the tire slowly while you view it at a tangential angle, watching for any "bubbles" in the tread.
    – Daniel R Hicks
    Commented Aug 23, 2012 at 15:48
  • You might also have a bit of moisture in between tire and tube. This can make a strange sound and it would happen once per revolution. Easy to check and you might notice something else while the rubber is off.
    – Ken Hiatt
    Commented Aug 23, 2012 at 16:24
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    I checked the spokes, brakes, seating, and trueness. All of them are great. I also checked the entire surface of the tire and couldn't find any bubbles. Is it possible to have a bubble that is too small to be seen?
    – Apreche
    Commented Aug 23, 2012 at 16:30
  • Could it be a defective tire? IE a single air bubble below the surface that gets compressed and then releases giving you the sound?
    – Chef Flambe
    Commented Aug 27, 2012 at 21:33

2 Answers 2

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Ken Hiatt mentioned a wet spot between tire and tube, and I'd like to add something that have already caused me the same symptoms: the anti-puncture band.

In general, there is an overlapping zone of anti-puncture where one tip lays over the other. Depending on how they sit against each other, this might cause this noise. In my experience, this is also a cause of puncture, because the edge of the band can "cut" a groove into the rubber and eventually puncture it.

I wouldn't discard, for the sake of completeness, something inside the rim if it is double-walled (sand, nipple, whatever), or perhaps something related to the loading/unloading of some spoke when the bike rolls with your weight over it.

Hope this helps!

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  • Yeah, certainly spoke noise can be devilishly difficult to suss out.
    – Daniel R Hicks
    Commented Aug 23, 2012 at 17:05
  • What's interesting is that the OP describes the sound as a "sticking/unsticking" noise, which is EXACTELY how I felt the noise caused by anti-puncture. Not sure if the OP uses anti-puncture, though...
    – heltonbiker
    Commented Aug 23, 2012 at 17:15
  • I do not have anti-puncture strips, but the tire is a very durable tire for NYC streets. I will take it off and check it out when I get home. The biggest problem is the sound is so feint, yet still audible. I might just keep biking and ignore it.
    – Apreche
    Commented Aug 23, 2012 at 20:14
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    @heltonbiker -- I've gotten similar noises from spokes.
    – Daniel R Hicks
    Commented Aug 24, 2012 at 1:53
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As JohnP mentioned, it sounds like your wheel may be rubbing against the brake. If you spin the wheel and look at the rim, do you notice one of the brakes getting closer and further from the rim as the wheel turns? If so, a few things to look at:

  • Your wheel may not be seated evenly in the dropouts.

  • Your wheel may be slightly out of true.

  • Your brakes may not be centered evenly.

Any or all of these could be contributing to the problem.

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