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Old 02-09-08, 06:01 PM   #1
jberenyi
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Calling On Expert Wheelbuilders

I have a new set of Mavic Open Pro Rims with new Record hubs that are running true to less than .005 laterally and radially. However, after checking all spokes on my rear wheel with my trusty Wheelsmith tensiometer I noted some tensions on a couple of spokes that are low and below minimum to Wheelsmith's conversion chart. Below is a chart that shows what they are and I'd like some expert opinion on it. Mavic Open Pro's need to be 90-110 Kgf on the rear right. We all know the left side will be lower but what is acceptable and am I okay with my findings?
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Last edited by jberenyi; 02-09-08 at 06:42 PM.
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Old 02-09-08, 06:32 PM   #2
Peedtm
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The NDS tension will be determined by dish, and how much you need (less dish=more tension) The three out of sync would worry me. You should shoot for no more than 10% variance. If you're fat, you'll break lots of spokes like this.
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Old 02-09-08, 06:34 PM   #3
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In 2 of the 3 low tension spokes you have adjacent spokes on the same side that are above average tension. In the 3rd case, it's the opposing spoke that's higher than average.

It's entirely possible to have a wheel which is true both radially and laterally yet has unacceptable variations in spoke tensions. It looks to me like that's what you have here. If it was my wheel I'd try getting the spoke tensions closer to equal then do a final trueing by tightening and loosening opposing spoke pairs by an equal amount.

Good luck.
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Old 02-09-08, 06:45 PM   #4
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The dish on the rear wheel is spot on. I loaded a radar plot above. Is it still possible to average out the tensions on the left side and keep the wheel true?

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Originally Posted by Peedtm View Post
The NDS tension will be determined by dish, and how much you need (less dish=more tension) The three out of sync would worry me. You should shoot for no more than 10% variance. If you're fat, you'll break lots of spokes like this.

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