# How to fix a hop in my wheel



## topflightpro (Nov 3, 2004)

I just bought a used Powertap set up. The powertap is built into a set of FSA RD-200 wheels. 

The rear wheel has a hop in it that I didn't notice before I bought the wheels. What, if anything, can I do to make the wheels perfectly round again?


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## JCavilia (Sep 12, 2005)

Radial truing is a little trickier than lateral truing, but the basic principles are the same: more spoke tension pulls the rim in that direction, reduced tension lets it spring the other way. Here are some guides that might help:
http://www.parktool.com/repair/readhowto.asp?id=81
http://www.sheldonbrown.com/wheelbuild.html#tensioning

One caveat: if a rim is damaged, it can be hard to get it perfectly round and still have even spoke tension. Uneven tension can make a wheel weaker and less stable. Since your wheel is used, you may have your work cut out for you. But if the hop isn't extreme, you should be able to improve it at least somewhat.


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## rruff (Feb 28, 2006)

If the hop is rather sharp then it is essentially a dent... and if you want to make it a good wheel, the rim will need to be replaced. If it is gradual, then try loosening all the spokes a few turns and rebuild the wheel... focusing on radial trueness rather than tension balance, until final tension is reached.


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## topflightpro (Nov 3, 2004)

Thanks for the info so far. 

Just to clarify, it's the rear wheel with the powertap hub that has the hop.


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## lawrence (May 17, 2005)

What I'm going to say first is a contentious point and subject to disagreement, argument on this website.

1) I wouldn't true a wheel without checking spoke tenion with a tensionmeter.

2) To remove the hop, if it's pulled in, the spokes over that area are too tight. If the hop is outward, the spokes are too loose. Generally people tighten spokes when wheel truing so the hop is probably in. You generally have to adjust at least 2 spokes and usually some more spokes on each side of the hop. If it's too tight, you loosen the immediate spokes, then as you progress away, you loosen those spokes less and less as you proceed away.


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## Kerry Irons (Feb 25, 2002)

*Un-hop*



topflightpro said:


> Thanks for the info so far.
> 
> Just to clarify, it's the rear wheel with the powertap hub that has the hop.


As others have said, assuming the rim is not damaged, it is fairly straightforward. You can check spoke tension quite easily by just "tonking" each spoke with an allen wrench or other small tool. If the spokes are loose (lower note when you tonk them) under a high spot, tighten them in pairs, groups of 4, groups of 6 as needed (always an even number). If the spokes are tight (higher note when you tonk them) under a low spot, loosen them in pairs. If this is not the case, then you may have to live with a wheel with either a hop or uneven tension. Lawrence tells you that you need a tensiometer. I've built 200 wheels over roughly 40 years and never used a tensiometer. You can choose the advice you want to take


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## android (Nov 20, 2007)

And don't forget that if the hop is near the joint, it may be impossible to get rid of it completely.


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## BenR (Dec 14, 2001)

*another no tensiometer vote*

Are they nice? Yes. Absolutely necessary? Not in my opinion. First investment should be in a solid truing stand. I've built a few wheels using 28-36 spoke, non-exotic parts. They turned out fine and were approved by the local wheel guru, despite a mechanic (Yours Truly) who has learned several lessons the hard way. But like Lawrence alluded to, it's easy to jack up the tension too high if you aren't paying attention, both while building and truing wheels. 

It's always good to go back and squeeze, tonk, or pluck a few spokes to refresh your memory of what proper tension feels/sounds like before making changes. Of course if the wheel is already completely messed up from past fiddling and you don't already have a good idea of what's normal, it's possible to progressively become farther and farther off whatever is appropriate - could always compare with a similar wheel. If all else fails, you go knock on Lawrence's door with a 6 pack and beg to borrow his tensiometer.

Kerry "tonks" and I was taught to "pluck" with a finger. Both work fine.


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## BenR (Dec 14, 2001)

*sure it's a hop?*

Might be a balance issue (many rims are heavy at the weld on the side opposite from the valve hole) or an out of round or improperly seated tire that's causing an optical illusion - definitely worth a recheck before turning nipples


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## MR_GRUMPY (Aug 21, 2002)

Why don't you just take it into a shop that you trust, and pay them $20-$30 to true it.


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## brujenn (Nov 26, 2007)

Are you seeing the hop with the tire on, or off? I had a poor quality tire that hopped over and 1/8 of an inch. Check the rim with out the tire - if you haven't already.


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## Mr. Versatile (Nov 24, 2005)

MR_GRUMPY said:


> Why don't you just take it into a shop that you trust, and pay them $20-$30 to true it.


 Are you kidding??  Not on your life. Never happen when I get a chance to play with nipples.


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## BenR (Dec 14, 2001)

Mr. Versatile said:


> Are you kidding??  Not on your life. Never happen when I get a chance to play with nipples.


Just be careful about which nipples you play with and always hedge on the gentle side of things until becoming more familiar with said nipples, otherwise your evening can go bad pretty quickly


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