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I just got a set of new carbon wheels on the cheap, Planet-X 50mm tubies.

I put a cassette on and put the wheel in the bike on the bike stand. When I spin the wheel, there is only a tiny hop, maybe 1mm, vertically in the wheel, but it causes a noticeable amount of....movement?......in the bike when spun up to speed on the stand, bike sort of starts hoping up and down a bit.
Then I put a new Conti GP4000 tubie on it to stretch, put it on straight, and pumped it up, and wow, it seemed to amplify the problem. When spun up to speed, the bike is bouncing up and down off the work stand!!

Is this somewhat normal, and will it be unnoticeable while actually riding????
 

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The "hop" you are referring to means that the wheel is ever so slightly out of true radially. A decent bike shop should be able to fix this for you for about thirty bucks or so, although the amount you describe would be acceptable to most people. This has nothing at all to do with the bike "bouncing" as you describe, which is indeed a consequence of the wheel being unbalanced. This is fairly normal, and most people don't give this a second thought, as it is harmless. It's mostly caused by the extra weight of the valve stem. Don't worry about it.
 

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Pirx said:
The "hop" you are referring to means that the wheel is ever so slightly out of true radially. A decent bike shop should be able to fix this for you for about thirty bucks or so, although the amount you describe would be acceptable to most people. This has nothing at all to do with the bike "bouncing" as you describe, which is indeed a consequence of the wheel being unbalanced. This is fairly normal, and most people don't give this a second thought, as it is harmless. It's mostly caused by the extra weight of the valve stem. Don't worry about it.
Yes :thumbsup:
 

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Just as an add-on: almost all bikes hop up and down if spun up in a repair stand. But the force that causes that is very small. There's no way that tiny force would be able to lift a bicycle with a rider on top of it. As said, you'll never notice it on the road.
 
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