Getting Even Spoke Tension?

Art-<< My rear wheel is tight, true and round. But spoke tension is not entirely even. >><BR><BR>

I wonder if the tension is overall a wee bit low?

Just asking-

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Someone will surely correct me if I'm wrong; but perfectly "even" spoke tension cannot be achieved.
Why? Because of the rim joint. The rim joint is stiffer than the rest of the rim, so the tension
"there" is always higher. At least that's always been my experience (been building the spoked wheel,
professionally, since 1969, motorcycle; bicycle since 1986.)

Art Harris said:

My rear wheel is tight, true and round. But spoke tension is not entirely even. I seem to have at
least one slightly "low" spot (near but not at the joint) where, in order to get roundness,
tension has to be low in a couple of spokes. At various other places around the wheel, some
individual spokes are somewhat tighter than others.

The wheel in question uses 36 spokes (DT 15 straight x 15-16-15), Sun M13II box section rim,
Dura-Ace 9-sp hub.

I've built several wheels over the last 20+ years with good results, so I'm not a newbie.

Is there a technique for equalizing spoke tension (in a wheel that is already true) without
screwing up trueness?

Thanks, Art Harris

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"Art Harris" <[email hidden]> wrote in message
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Quoted message said:

My rear wheel is tight, true and round. But spoke tension is not entirely even. I seem to have at
least one slightly "low" spot (near but not at the joint) where, in order to get roundness,
tension has to be low in a couple of spokes. At various other places around the wheel, some
individual spokes are somewhat tighter than others.

The wheel in question uses 36 spokes (DT 15 straight x 15-16-15), Sun M13II box section rim,
Dura-Ace 9-sp hub.

I've built several wheels over the last 20+ years with good results, so I'm not a newbie.

Is there a technique for equalizing spoke tension (in a wheel that is already true) without
screwing up trueness?

Thanks, Art Harris

I've noticed this myself with other Sun rims, the Rhyno Lite and Singletrack. Either they aren't as
round as other rims to start with or there is variation in the extrusion process that creates 'soft'
spots. Not knowing any better I've just lived with the results.

Mike

is the wheel true and round in the stand after stressing it? When it remains true after fair
stresses, then the spokes are probaby at their optimal tension. If just a few spokes are less than
expected by whatever method you're using, then there are a number of factors to consider, from
nipples to lube that are probably not worth hunting down. There is a possibility that yours might be
low globally, in which case stess-recheck-true-stress recheck will sooner or later get you to the
right place. If there are significant variations in a true wheel, and difficulties getting there,
then the rim is shot. "Art Harris" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

My rear wheel is tight, true and round. But spoke tension is not entirely even. I seem to have at
least one slightly "low" spot (near but not at the joint) where, in order to get roundness,
tension has to be low in a couple of spokes. At various other places around the wheel, some
individual spokes are somewhat tighter than others.

The wheel in question uses 36 spokes (DT 15 straight x 15-16-15), Sun M13II box section rim,
Dura-Ace 9-sp hub.

I've built several wheels over the last 20+ years with good results, so I'm not a newbie.

Is there a technique for equalizing spoke tension (in a wheel that is already true) without
screwing up trueness?

Thanks, Art Harris

deegan said:

is the wheel true and round in the stand after stressing it? When it remains true after fair
stresses, then the spokes are probaby at their optimal tension. If just a few spokes are less than
expected by whatever method you're using, then there are a number of factors to consider, from
nipples to lube that are probably not worth hunting down. There is a possibility that yours might
be low globally, in which case stess-recheck-true-stress recheck will sooner or later get you to
the right place. If there are significant variations in a true wheel, and difficulties getting
there, then the rim is shot.

Yesterday, I took the tension down and slowly brought it back up, alternately checking roundness and
trueness. It's true within about .25 mm, and round within +/- 0.5 mm. Spoke threads and rim eyelets
are lubed, and overall tension is good. Most spokes are at about the same tension (determined by
plucking).

But there are still a few spokes above and below the tension of the rest. And they're the same
spokes that were hi/lo before. So I think I have a sick rim. I had played around unsuccessfully
trying to equalize tension while maintaining true. BTW, I built this wheel about two years ago, and
it's got a few thousand miles on it.

My rim's ERD is 610 mm, so I think I'm going to replace it with a Torelli Master (611 ERD) and see
how that works out.

Not sure what you mean by "low globally." Do you mean low overall tension?

Thanks, Art Harris