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Old 06-17-11, 12:54 PM
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gyozadude
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Bikes: Bridgestone RB-1, 600, T700, MB-6 w/ Dirt Drops, MB-Zip, Bianchi Limited, Nashbar Hounder

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Your tensions seem good. I might tighten the drive side a touch, especially on 8/9/10 spd gearing with more acute dish. But you're clearly within a good range. Your variance seems good too.

Note also that variance in tension can be caused by many factors beyond your control. E.g. What spokes are you using? DT competitions? Double butted? I've got some older sets of spokes and just by hand feel, the stiffness and location of the butting can vary significantly.

Most tensiometers have quite a bit of error, too. And rims in their natural state can have some imperfections out of round. This means you can sum up the variances and find more than 10 - 15% variation. I expect that in the measurement. My key indicators on a build are the run-out in roundness. And second is the lateral true run out. If you have less than 25% measured variation in tension on a new rim and it's round and true to less than 1mm either way, the rest of the slack is going to be picked up by the tires (which have variation in height/width). In addition, if the profile of the rim is aero, or semi-aero, depending on the mfg., small tolerances in round require great variance in tension to pull back into true round.

One of the keys to distributing tension properly is to remove wheel after each round of tensioning and apply lateral load on the rims with both hands working around the rim, then flip wheel over and repeat (aka 'ping' the wheel). Then round/true/repeat. If you find a low spot (too tight), try to always loosen a group of 4 spokes in that group (assuming 3/4 cross lacing), ping the wheel, then repeat check for round/true. But I assume you already have done that to get to this state.

Lastly, after the 3rd or 4th iteration, I'm usually quite happy with a wheel and I install rim strip, tube, tire, and inflate. The real test is to ride the wheel under load for a mile or so. This works and seats everything into what is really close to the final state of the wheel. I then take that wheel out, remove tire/tube and then recheck tension and do a final tension/true. While a wheel never seems to be able to re-distribute tension perfectly in a shop, there's nothing like a ride with a real person to put that wheel to the test and come back with any loose spokes. Must be Murphy's Law or something! LOL! But the great part is that I find that post-first ride re-tensioning to be sort of the magical opportunity to put the wheel into a final stable true that will last a long time (or until accident ruins the wheel).
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