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my rear wheel has a constant bump whenever I ride . I've done all that came to mind at firs. Deflated and checked the tire , checked the axel for bends , checked the ball bearings , made shure the break is not rubbing and that the wheel is properly tightened on the frame .

One thing I did notice is that when I spin it in my hand I can feel the ball barings sort of lightly scratching with the axel ? I know that can be a problem for them but could that also cause that constant bump ? Any solution you have would be welcomed to check out .

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  • did you check the rim if it's symmetrical? i.e. spoke on one side is longer than the opposite one
    – Nhân Lê
    Commented Aug 27, 2015 at 8:51
  • Yes , the wheel it true if that is what you mean Commented Aug 27, 2015 at 9:45
  • so the rim is true laterally and radially? So how do you figure out whether it has a constant bump?
    – Nhân Lê
    Commented Aug 27, 2015 at 10:10
  • I mean from riding, or from lifting the wheel and let it spin so that you can feel the tumbling effect?
    – Nhân Lê
    Commented Aug 27, 2015 at 12:12
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    When you feel a "bump" that usually means that there is a bump in the tire. Spin the wheel and watch one spot from the side, in a location where you can "sight" against a bit of the frame so your eyes have a reference point. Look for a bulge in the tire. Commented Aug 27, 2015 at 12:30

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Have you recently replaced a tire or tube? If so, then the tire may not be properly seated.

Remove the wheel, hold it in your lap lying flat, and rotate the wheel around looking at the edge of the rim and tire. You are looking for a "low spot" where the tire appears to "disappear" down into the wheel. It will be slight, but it doesn't take much. My old road bike has 27x1 (630x25) tires, and they can be a challenge.

If you find a "low spot", deflate the tube, put a little bit of dishwashing soap and water on the tire at the bead, and inflate the tube. You may hear a pop sound when the tire bead seats properly into the wheel.

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    No need to remove the wheel. Commented Aug 27, 2015 at 22:43
  • Will give that a try and come back with findings later in the day Commented Aug 28, 2015 at 8:38

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