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Old 10-05-06, 09:12 AM   #1
recneps
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How to 'round' a wheel

Something I never got a grasp, how do you round a wheel.

Ive heard two different explanations.

One is to find the spot that is low. On the truing stand the part of the wheel that sticks out. and loosen a good number of spokes on that side of the wheel if its a 36h wheel loosen ~12. then tighten ~12 spokes on the oposite side of the wheel. This should take out the 'hop"

Two find the low spot or the spot in the rim thats sticking out and tighten the spokes around the low spot effectively pulling the rim towards the hub and eliminating the hop.

also when round or even trueing a wheel is it a better Idea to take the tire off?
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Old 10-05-06, 09:21 AM   #2
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Read over Sheldon Brown's wheelbuilding page, at
http://www.sheldonbrown.com/wheelbuild.html
Start at "initial spoke adjustment" about 2/3 of the way down.

I usually round out a wheel while also adding tension, so I focus on the parts that stick out too far from the hub, and tighten those spokes. I recommend tightening only a few spokes, instead of 12 at a time.
If the wheel already has full tension, you'll need to loosen spokes on parts where the rim is too close to the hub.

And yes, it's basically necessary to take the tire off when rounding a wheel especially; for side-to-side truing the tire doesn't get in the way as much.
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Old 10-05-06, 09:39 AM   #3
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If the wheel has quite a bit of tension in it, I will relieve all spokes one full turn before I begin. That way I have more tension to work with.

Wheels will often be out of round in both directions. That is in and out.

What I do is find the worse section and work it first. Often I will look for "in" problems first because they can be alleviated by removing tension.

Once I have done what I can with the In problem, I look to the out problem.

My technique is to find the bump or divet and then start with the spokes one away from the beginning of the dip or bump. Always starting on one side and finishing on the other. Each spoke at either end gets 1/4 turn and all in between get 1/2 turn. For the smaller than 4 spoke run. I improvise. But I always am aware of the overall effect to the dish and trueness.

NOTE - This is my first shot at putting this technique into words. It is a tough one. I apologize if my description confuses the issue. But see me do it once and everyone understands.

I learned the basic technique at a mechanics school long ago. It works.
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Old 10-05-06, 12:15 PM   #4
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First, for rounding you really should have a truing stand.

Method one. Identify high or low spots.
For a high spot, mark it with tape tighten it and loosen every other spoke. For a loose spot, do the opposite.

Caveat, if your dealing with a really tight wheel you should only loosen things.

Method 2:
This method is more appropriate for a wheel that has lot of hops and flats. Just go along in quarter turns along each spoke. If the spot (according to your gauge) is low, then loosen, if it's high tighten, if it's even leave it along. Keep going around until you get within a millimeter.

After either method, you will have to do some more lateral truing. Than you'll probably have to do a vertical (rounding) true again. Make sure in your final steps that you untwist each spoke by overtwisting it and then bringing it back where you want it.
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