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Wheel questions

  1. Jan 31, 2015 #1

    When I walk side by side the kickbed scooter without standing on the scooter, the front wheels moves and back wheel does not. When I stand on the scooter and use it at usual, it moves, though not as fast as before.

    I am wondering if this has anything to do with bearings but I thought maybe it would make sense to get a better idea of how wheels work in general.

    1. What are some things I should try?

    2. What could be some reasons the back wheel seems to not roll as well and

    3. What products should I use or who should I show the scooter to who can diagnose the problem?


    Front wheel


    Back wheel doesn't roll as well as it used to
  2. jcsd
  3. Jan 31, 2015 #2
    Short version:

    In a two wheel device, if one wheel turns more easily than the other, why? What parts are in trouble and what should be done?
  4. Feb 1, 2015 #3
    Is the rear brake rubbing until you stand on the platform and then the brake unloads?
    You may possibly have bearing issues in the rear
  5. Feb 1, 2015 #4
    >Is the rear brake rubbing until you stand on the platform and then the brake unloads?


    Also I have almost never used the break.

    What are some next steps to diagnose the problem?
  6. Feb 1, 2015 #5
    If the brake isn't dragging, disassemble the rear wheel
  7. Feb 1, 2015 #6
    Part of the problem is my vocabulary and understanding. Why do we talk about the break? I never use it and never intend to use it. I don't know what "break dragging" means either. If I had to guess, I would bet the break isn't the problem because I never use it.

    The rear wheel doesn't move. Unless you push on it very hard. I imagine something somehow gunking up or stuck inside some part of the wheel or some part of the wheel doesn't roll well because something is worn down. I bet the snow/mud I went through has something to do with it but I am not sure.

    I've been looking for a good animation and picture to explain how wheels work especially the inside but still don't understand. What kind of things do you use to dissasemble a scooter wheel or is that even the right course of action.

    Evidently there are these giant magical balls inside of the wall that somehow make it roll better? How do you damage bearings?

    http://www.youblob.com/content/bearings-explained [Broken]

    Last edited by a moderator: May 7, 2017
  8. Feb 1, 2015 #7
    If the brake is touching the wheel while the wheel is trying to move, the wheel won't move as fast as it would if it spins freely.

    I think you might be right.

    The "giant magical balls" in a bearing help with rolling because there's not as much rubbing together to cause friction. The balls theoretically only touch at a single point (in reality the balls flatten a tiny bit) so things can spin more freely. There's lots of different types of bearings, but the main idea is to reduce parts rubbing together (friction).
    Last edited: Feb 1, 2015
  9. Feb 3, 2015 #8


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    1) Keep in mind that walking side by side means pushing the top of the handle, this transfers torque around the front wheel, which means a small torque will be transferred to the rear wheel trying to push it up. the bigger the front wheel friction, the greater the transfer of torque. For visualization just block the front wheel via a rock in front and push it by the handle forward. So a big culprit could be your front wheel friction (bearings, etc.)

    2) Rear wheel friction (bearings, etc.), easily tested by spinning it and observing the time it takes to slow down. (I don't know how to tell you to measure this, but you can compare with the front wheel)
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