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Zipp Question
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Anyone ever dealt with a wheel that appears "warped" or off as it rotates? I don't mean a left to right wabble. Rather as it rotates, it seems to go smooth, and then slow a bit, and then smooth again (all in one revolution).... almost like its oval. It isn't noticable when cruising but when you just spin the wheel when the bike is still, you notice it. Feedback welcome, how to fix? Is it normal?
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Re: Zipp Question [Bell] [ In reply to ]
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is it a tubular? Some times you get a little hump in the tire, not sure why but it is common with tubulars. Don't know how old it is but send it back.
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Re: Zipp Question [bjdbike] [ In reply to ]
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Ya its tubular...don't think thats the issue. I just put new ones on this week. Its like part of the wheel is more weighted than the rest, causing a lull in the rotation (albeit a minor lull).
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Re: Zipp Question [Bell] [ In reply to ]
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Not a big deal...pretty common. I have a similar effect in mine. Had it with my previous tires and now with my newly installed ones...
Last edited by: PlacidPirate108: Jun 12, 08 21:23
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Re: Zipp Question [Bell] [ In reply to ]
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Heavier at the valve.
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Re: Zipp Question [SucabStunna] [ In reply to ]
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I don't see how this would effect the angular velocity as the moment of inertia of the wheel would not be effected by one area being heavier than the other... unless... the heavier valve area had a changing radius which would mean it is also out of true.

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Re: Zipp Question [Bell] [ In reply to ]
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Have you just never spun a wheel before? There's a reason LEW specifically counter-balances their wheels...

Every wheel does this. They're not uniform structures (a valve hole makes that impossible), so they'll obviously have a bias.
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Re: Zipp Question [Bell] [ In reply to ]
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yup, pretty normal, my zipps do the same thing... they are not quite perfectly balanced which as others noted is near impossible in a stock build because of variables such as tire type, tire consistancy, length of the valve stem, length and type of the valve extender... you can balance them with stick on lead weights if you want to but bicycle tires have a pretty low relative rpm so the small imbalance doesn't affect their performance all that much.
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Re: Zipp Question [Tai] [ In reply to ]
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Nice. Glad to hear the feedback. Thanks for the explanation, much appreciated!
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Re: Zipp Question [msuguy512] [ In reply to ]
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I think you mean product of inertia


Ryan
Engineer. Duathlete. Roadie. Human.
CAPA Cycling
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