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Old 02-13-08, 07:17 PM   #1
George
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I got a dishing tool

I had my wheels in pretty good shape, but I ordered a dishing tool to make sure everything was all right. I loosened all the spokes on the back wheel and started from scratch. After I got both sides down to around 45#, I started dishing the wheel. I had to pull the drive side over about an inch. I kept taking half turns, then taking the wheel off the truing stand and using the dishing tool again. After doing this several times I finally got the wheel centered. Now comes the problem, by the time I got it centered, I have the drive side up to 137# and the non drive side is anywhere from 51# to 76#. If I pull the ND side up the spokes on the drive side will be to tight. If I put some slack on the drive side and take up the ND side the wheel wont be dished right. I hope somebody can tell me what to do. I worked on it for 6 hours yesterday and another 4 hours today.
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Old 02-13-08, 07:40 PM   #2
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That seems like an awfully big tension differential. What do you mean by #? That's usually a pound symbol.
The 9 and 10-speed wheels that I've worked on have the non-driveside spoke tension at about 65% of the driveside spoke tension. Tension numbers are usually shown in kgf.
I dish my wheels by reversing the wheel on the truing stand several times until the rim fits the calipers equally on both sides. I don't have a dishing gauge.

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Old 02-13-08, 08:11 PM   #3
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I should have said they a Mavic Open Sport. I'm sorry I used the wrong terminology, yes it is 137kgf and 51 to 76kgf.
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Old 02-13-08, 08:45 PM   #4
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You should double check your spoke lengths and make sure you're using the dishing tool correctly. Most people have a reverse idea of what the dish stick is telling them to do.

If the dish stick tells you that it's supposed to go this way and you do the supposed fix - reverse it in the stand. The dish should get better not worse. Are you stress relieving?
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Old 02-13-08, 09:22 PM   #5
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Yes I did stress relieve it and every time I used the dishing tool I flipped the wheel and adjusted the tool again. I read just about everything there is to read on this and it's really got me pulling my hair out.
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Old 02-13-08, 09:31 PM   #6
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Do you have instructions for how to use the tool?
If not you might try the Park Tool site.
http://www.parktool.com/repair/readhowto.asp?id=82

Al

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Old 02-13-08, 10:07 PM   #7
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That is a really big tension differential. I usually see 55%-75% on modern hubs. The 75% would be for an off-center spokeline on the rim (Aerohead OC).

How true is the weel? If it's out of true a couple mm, you can't really check dish reliably. You should check dish at several points around the wheel.
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Old 02-13-08, 10:39 PM   #8
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The wheel is centered in the stays on the bike and I'm off that much with the tension. I'm going to try and put a little more tension on it tomorrow without throwing it off, I hope.
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Old 02-13-08, 10:45 PM   #9
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The wheel is centered in the stays on the bike and I'm off that much with the tension. I'm going to try and put a little more tension on it tomorrow without throwing it off, I hope.
I wouldn't use this (your frame) as a guage although the wheel ultimately needs to be dished for it whether or not it's straight
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Old 02-14-08, 07:29 AM   #10
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Yes I did stress relieve it and every time I used the dishing tool I flipped the wheel and adjusted the tool again. I read just about everything there is to read on this and it's really got me pulling my hair out.
Just trying to understand what you're saying here. You say you "adjusted the tool again." You should only adjust the tool once per check. Loosen the marker, ends on rim, tighten marker so it's on the axle's locknut. Flip the wheel, place the ends on the SAME PLACE in the rim and see if the pointer is touching the lock nut first or the ends are touching the rim first.

It's important to use the locknuts, not the axle ends. It's also important to use the same two spots in the rim. Note that you only have to track one spot, because the other end can only go to one place if you're on the same side of the locknut.
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Old 02-14-08, 09:30 AM   #11
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[QUOTE=waterrockets;6163399 " You should only adjust the tool once per check. Loosen the marker, ends on rim, tighten marker so it's on the axle's locknut. Flip the wheel, place the ends on the SAME PLACE in the rim and see if the pointer is touching the lock nut first or the ends are touching the rim first.

It's important to use the locknuts, not the axle ends. It's also important to use the same two spots in the rim. Note that you only have to track one spot, because the other end can only go to one place if you're on the same side of the locknut.[/QUOTE]

This sounds like whats wrong
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Old 02-14-08, 11:23 AM   #12
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I will try that, I was using the axle ends. I've been working on this for another 3 hours this morning. I could take it to the LBS, but it's something I want to get. It'll probably kill me, just kidding I hope. Thanks for the help and I'm going to try again, right now.
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Old 02-14-08, 11:43 AM   #13
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Are you sure you got the axle assembly right; I mean have you got the washers and spacers on the appropriate sides (not inversed?) Obviously, this will make a huge difference with regard to centering. Check on the shimano tech pages if any doubt.
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Old 02-14-08, 12:05 PM   #14
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Get the wheel in perfect shape first. It should be well centered, well dished and true. Do not bother about spoke tensioning before the wheel is nearly perfect.

Then slowly increase spoke tension by small increments (1/4 turn). Complete one side then the opposite. Stress relieve and check the wheel after handling both sides.

If all is OK repeat the process.
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