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Riding my bike within my suburban residential neighborhood, I felt a shock, like a snap although I don't think anything snapped, followed by a rubbing noise every few seconds. Pedaling and the brakes continued to work.

I pulled over and examined my bike, starting with the brakes, and discovered that the left side of the rear tire now rubs against the left chain stay at one spot, near the tube valve stem. The wheel/tire is perfectly centered everywhere else along its circumference, just not there.

I've had this bike for about a year (bought at Goodwill), and, aside from a break over the winter, I've been riding it at least once a week, and I can tell you that this didn't happen before.

I haven't done any hard riding recently; I've been taking it easy as I build back up from my winter break.

The tire is seated correctly on the rim, as far as I can tell.

I didn't count the spokes off one by one, but looking at where they each meet the rim, they seem to all still be intact. There weren't any dangling off or obviously snapped away.

The bicycle is an old Univega hybrid bike with 700c Bontrager tires. I'm no expert, but I'd describe the tires as road tires, about an inch wide.

I'm stumped for what's caused it or how to fix it.

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    Try wiggling all the spokes. They usually break at the hub. Maybe one broke but the lacing pattern is holding it in place?
    – freiheit
    Apr 4, 2013 at 23:46
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    Yeah, if you check the spokes to see if they're tight almost certainly one has broken. Your description of the event is exactly what you feel when a spoke snaps. A bike shop should be able to fix you up for only a modest fee.
    – Daniel R Hicks
    Apr 5, 2013 at 0:19

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Check the spokes - its likely one or more has broken ("I felt a shock, like a snap....".). The ones to check are ones that got from the rim, where the rubbing is occurring, to the hub on the opposite side of the rubbing (in your case, the right side of the hub). If these have let go, there is nothing stopping the rim being pulled to the left.

It may be that these are loose, not broken, although it unlikely. If the spokes are not broken, you might be able to straighten the rim by tightening the right side spokes and if needed, loosening the left side ones. It's not too hard if the rim is not too far out of true, but needs patience for a novice.

If there is a broken spoke, or the rim is a long way off and cannot be "tweaked" it will be worth taking to your LBS to get them to look at it. As it's only a year old, spokes should not be breaking.

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  • He said he got it from Goodwill about a year ago. No telling how old the bike is.
    – Daniel R Hicks
    Apr 5, 2013 at 0:27
  • Probably much older; when I did some casual web-searching for Univega, I don't think I saw anything after the 1990s. Of course, however old the bike is, the wheel might not be original, so I've no idea how old that is, either. I'll take a look tomorrow.
    – Peter Hosey
    Apr 5, 2013 at 1:59
  • Well, damn. Guess this bike's benched until I can get that fixed. Thanks.
    – Peter Hosey
    Apr 5, 2013 at 19:42
  • Ah, Univega... that is a vintage bike! But a good one in its time.
    – nogasbiker
    Aug 12, 2016 at 20:49
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A snap, causing a rubbing noise "every few seconds" indicates that you popped a spoke. A broken spoke might not be apparent at a glance because sometimes the broken end of the spoke stays near its place of origin. Spokes usually break right at the hub, at the little elbow where they bend to enter the hub, where they take a lot of stress. More often than not, they break on the drive side (where the cogs are).

On a bike with horizontal dropouts or rear-track fork ends, another cause of rubbing can be that the wheel axle has slipped due to the nut loosening. That rubbing is not intermittent, however; if the wheel is true, it is constant. It can also severely hinder the bike, making it near impossible to ride. Usually when this happens, the wheel slips forward on the drive side due to chain tension. On rear-track fork ends, if a chaintug is installed, it could mitigate the problem.

Finally, another cause of rubbing can be a snapped wheel axle. Astonishingly, it's not impossible that a bike which uses axle nuts to tightly a wheel to the dropouts can still be somewhat ridden with a broken rear axle. The two broken pieces of the axle are so rigidly attached to the frame with the nuts that they somewhat support the wheel anyway.

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