Chain ring wobble.
#1
Thread Starter
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From: NW Ohio
Bikes: 1983 Univega Super Strada, 1986 Panasonic DX5000, 1984 Fuji Team 85 Univega Gran Turismo, 1984 Lotus Unique, 1987 Centurion Expert, 1987 Centurion Ironman Master,
Chain ring wobble.
I've noticed my Specialized Sequoia's chain ring has a slight wobble to it. It
doesn't seem to affect the way it rides or shifts. It shifts very smoothly. Do you
think this would be corrected if I removed the cranks and turned them 45 degrees on the axle
or should I just leave it alone?
doesn't seem to affect the way it rides or shifts. It shifts very smoothly. Do you
think this would be corrected if I removed the cranks and turned them 45 degrees on the axle
or should I just leave it alone?
#2
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From: The Urban Shores Of Michigami
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I would rotate the chainrings instead of the crank.. It's less less harmful.
If the crank is bent, then it's bent and will wobble no matter what angle you rotate it.
If the crank is bent, then it's bent and will wobble no matter what angle you rotate it.
Last edited by branko_76; 05-22-20 at 07:40 PM.
#3
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From: NW Ohio
Bikes: 1983 Univega Super Strada, 1986 Panasonic DX5000, 1984 Fuji Team 85 Univega Gran Turismo, 1984 Lotus Unique, 1987 Centurion Expert, 1987 Centurion Ironman Master,
#4
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From: The Urban Shores Of Michigami
Bikes: ........................................ .....Holdsworth "Special"..... .......Falcon "Special".......... .........Miyata 912........... ........................................
#5
Master Parts Rearranger

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I'd say if it doesn't affect anything, take that blessing and keep on motoring. I've come across a few wobblers and they definitely did affect ride and shifting. Sometimes it's just the chain ring and other times it's the spider arm of the drive side crank. I've found out which (or both) by making a flag-ish shaped piece out of masking tape, sticking it to the seat tube where the tape nearly touches the chain ring (or spider arms) and spin the cranks. If the 'ring is bent, get a new ring. If the spider arm is bent, an ever so slight and gentle persuasion with the 'jaws' of a 12" Crescent wrench around the offending spider arm tab (where the rings bolt to/through) can ease things back. This is a Sheldon recommendation, and one I've used a few times to good effect. I'd rather not do it, but cranksets bend sometimes. As always, you do this operation at your own risk. And like I said before, if it ain't messin' with anything, let sleeping dogs lie.
#6
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I've noticed my Specialized Sequoia's chain ring has a slight wobble to it. It
doesn't seem to affect the way it rides or shifts. It shifts very smoothly. Do you
think this would be corrected if I removed the cranks and turned them 45 degrees on the axle
or should I just leave it alone?
doesn't seem to affect the way it rides or shifts. It shifts very smoothly. Do you
think this would be corrected if I removed the cranks and turned them 45 degrees on the axle
or should I just leave it alone?
The proper way to get rid of chainring wobble is to remove the ring and make it flat by itself, then re-install it. If it's not the ring that is wobbling then the crank arms or axle are likely bent - again, remove, fix, re-install. Rings are easy, usually stamped from sheet and bendable; cranks are difficult - good aluminium ones don't bend at all easily, much more likely to break instead (straightening steel cranks is a doddle). A bent axle is best replaced, unless you have a set of V-blocks and a hydraulic or good big lever press, a dial indicator, and a way to mount the axle between centres to check runout - got a lathe?
Last edited by oneclick; 05-23-20 at 02:08 AM.
#8
Extraordinary Magnitude


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From: Waukesha WI
Bikes: 1978 Trek TX700; 1978/79 Trek 736; 1984 Specialized Stumpjumper Sport; 1984 Schwinn Voyageur SP; 1985 Trek 620; 1985 Trek 720; 1986 Trek 400 Elance; 1987 Schwinn High Sierra; 1990 Miyata 1000LT
Is it a wobble or is it a non-round chainring? Like Biopace or Ovaltech?
The bigger rings are sometimes difficult to tell if they're non round- I just remember the first time looking down and seeing that.
I also remember a thread here where someone was aghast that a company would put out rings that went out of round.
The bigger rings are sometimes difficult to tell if they're non round- I just remember the first time looking down and seeing that.
I also remember a thread here where someone was aghast that a company would put out rings that went out of round.
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Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.
#9
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From: Toledo Ohio
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Probably not your problem on that pretty bike Robert, but I had some abused crank arms that I purchased at a bike co-op that had too much wobble. I think the square tapers were bad, and different rings and such would not make them useable. I tried what you mentioned, although, I am sure you meant to rotate 90 degrees with no luck. Perhaps you have tried this, and I think Sheldon Brown advises this.
i am now reluctant to take the cranks off too many times for fear of distorting things. If possible, I make an index mark with a marker so as to put back on in the same orientation. I just installed my first sealed BB, so those cranks shouldn’t have to come off for a long time I hope.
i am now reluctant to take the cranks off too many times for fear of distorting things. If possible, I make an index mark with a marker so as to put back on in the same orientation. I just installed my first sealed BB, so those cranks shouldn’t have to come off for a long time I hope.





