resonating rear wheel?
05-31-22, 03:51 PM
#1
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resonating rear wheel?
Just noticed that when my bike is upside down (I don't have a work stand) and I pedal the rear wheel really fast (probably faster than I'll ever ride, like 50mph) the bike "bounces" up and down (as if a resonant frequency is hit). I tried the test with the tire removed and it behaves the same with and without a tire mounted (although the speed at which it occurs changes).
I checked and the wheel is trued vertically and laterally (with a Park truing stand). I can't get the wheel to do it in the truing stand, but that may be only because I can't get it up to the same speed. Putting the same wheel on another bike does the same thing it but isn't as pronounced (and seems to occur at a different speed).
The cassette doesn't wobble and there doesn't appear to be play in any bearings.
I haven't noticed this while riding (though 40mph is the highest I've gone downhill) but wanted to check if this is something to be concerned with.
This may have been like this all along and I never noticed it probably because I never shifted to the hardest gear with the bike upside down and tried it.
My guess is I'm hitting some sort of resonant frequency on the bike and it will likely go away when I'm on the bike as the damping will have changed.
I checked and the wheel is trued vertically and laterally (with a Park truing stand). I can't get the wheel to do it in the truing stand, but that may be only because I can't get it up to the same speed. Putting the same wheel on another bike does the same thing it but isn't as pronounced (and seems to occur at a different speed).
The cassette doesn't wobble and there doesn't appear to be play in any bearings.
I haven't noticed this while riding (though 40mph is the highest I've gone downhill) but wanted to check if this is something to be concerned with.
This may have been like this all along and I never noticed it probably because I never shifted to the hardest gear with the bike upside down and tried it.
My guess is I'm hitting some sort of resonant frequency on the bike and it will likely go away when I'm on the bike as the damping will have changed.
Last edited by Symox; 05-31-22 at 04:05 PM.
05-31-22, 03:56 PM
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It's not perfectly balanced. Don't worry about it.
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05-31-22, 04:10 PM
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I should have said, there are no reflectors or chain guard on the wheel
05-31-22, 04:52 PM
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Most all my bikes did the same thing when I spun the wheel really fast when upside down.
So?
So?
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05-31-22, 06:24 PM
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As long as you ONLY ride the bike when it’s right side up, you should be fine.
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06-01-22, 11:15 AM
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Thanks everyone for the help
