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  1. #1
    Member aaronpass's Avatar
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    Bicycle Suddenly Unstable??

    Riding home from work on Friday, my bike all of a sudden felt a little unstable. I thought it may just be me, but I rode it today again and it is still doing it. If I take my hands of the bars while moving, it feels like it is going to tip right over. Very difficult to ride with one hand as well...

    The tires are up to pressure, tires are in good shape. Anyone have any thoughts??

  2. #2
    RIP Sonny RaleighSport's Avatar
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    Simple check list I'd run down, check your handle bar to fork allignment, check your wheels positions mounted in their drop outs... and I guess (although I think it's unlikely) the crankset/BB to make sure they're tightened properly but I'm guessing you'd notice either of those with your feet already. Pictures might also help but who knows
    "Seriously is what I want to be, so I put on spandex and show off my gear, my junk, my thing, yes my ding-a-ling."

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    cracked fork/frame or axel

  4. #4
    RIP Sonny RaleighSport's Avatar
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    Quote Originally Posted by bobn View Post
    cracked fork/frame or axel
    :/ that's my fear too, but we can pray it's a quick simple fix no?
    "Seriously is what I want to be, so I put on spandex and show off my gear, my junk, my thing, yes my ding-a-ling."

  5. #5
    Member aaronpass's Avatar
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    Since I can feel it while riding, would it be noticeable? Visible to the eye?

  6. #6
    Humvee of bikes =Worksman Nightshade's Avatar
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    Quote Originally Posted by aaronpass View Post
    Riding home from work on Friday, my bike all of a sudden felt a little unstable. I thought it may just be me, but I rode it today again and it is still doing it. If I take my hands of the bars while moving, it feels like it is going to tip right over. Very difficult to ride with one hand as well...

    The tires are up to pressure, tires are in good shape. Anyone have any thoughts??
    Spoke check time!! IMO, I'm 99.9 % sure that you have one or more broken spokes in your rear wheel.
    My preferred bicycle brand is.......WORKSMAN CYCLES
    I dislike clipless pedals on any city bike since I feel they are unsafe.

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  7. #7
    Senior Member Looigi's Avatar
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    Check for a loose headset. Also, grab the top of the front wheel at the top of the forks and push it left and right to check for loose wheel bearings or cracked axle.

  8. #8
    Member aaronpass's Avatar
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    So I just walked downstairs and checked out the bike. No noticeable cracks in the frame or the fork. The spokes are all tight and in great shape. Wheels spin true.

    The headset is not loose but it does look like fork is tilted forward a bit... just slightly...

    The gap at the front of the headtube looks good, but at the back it gets slightly larger. New bearings needed?

  9. #9
    Senior Member Retro Grouch's Avatar
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    Quote Originally Posted by aaronpass View Post
    So I just walked downstairs and checked out the bike. No noticeable cracks in the frame or the fork. The spokes are all tight and in great shape. Wheels spin true.

    The headset is not loose but it does look like fork is tilted forward a bit... just slightly...

    The gap at the front of the headtube looks good, but at the back it gets slightly larger. New bearings needed?
    Hold the bike up on it's wheels, apply the front brake and try to rock the bike forward. Feel a click? If you do, that's it. Hopefully a headset adjustment will fix it.

  10. #10
    Senior Member Looigi's Avatar
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    Quote Originally Posted by Retro Grouch View Post
    Hold the bike up on it's wheels, apply the front brake and try to rock the bike forward. Feel a click?
    Yeah. Rock it back and forth with some force and listen, look, and feel for movement where the top of the fork abuts the head tube. Sometimes there might be some play or looseness in the brake caliper that might feel similar to a loose headset.

  11. #11
    Member aaronpass's Avatar
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    Well, I got home and checked the fork, frame and axel. All good.

    Then I pulled the fork out and the bottom headset bearing was destroyed...

    Glad my frame isn't cracked! Thanks for the help everyone!

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