On May 9, 10:44=A0pm, Ron Ruff <rruffrr...@[EMAIL PROTECTED]
> wrote:
> On May 9, 10:14=A0am, "joseph.santanie...@[EMAIL PROTECTED]
"
>
> <joseph.santanie...@[EMAIL PROTECTED]
> wrote:
> > There is some interesting stuff here:
>
> >http://www.geocities.com/spokeanwheel/lacingsr.htm
>
> It sure is interesting, but don't believe most of what you read on
> that site...
>
> > My main concern is lateral stiffness in the front, and lateral
> > stiffnes and torque resistance in the rear. I don't want the brakes to
> > rub when I am out of the saddle, and I certainly don't want the
> > occasional "boing" feeling I get with the rear wheel on my lightweight
> > wheels when I stand in =A0high torque conditions.
>
> Your light wheels have a narrow flange spacing and a light rim... this
> won't be the case with your aero wheels.
>
> > So radial in the front sounds like the way to go for stiffness. Heads
> > in. Pretty straight forward.
>
> Do you have 28 spokes in the front too? If so, you can lace it any way
> you want... it will be stiffer than the rear anyway.
>
> > What do you guys think about the 2x NDS, 3x DS recommended in the link
> > above? And the reasoning?
>
> That should be ok... but I'm not sure it is ideal. I think Dave said
> it well in the post above. If you have a torsionally stiff hub, then
> the NDS will be involved in torque transfer if it is cross-laced. This
> is good in that it reduces the amount that the DS needs to transfer...
> but bad in that the NDS spokes are more likely to go slack from
> combined torque, radial, and lateral loads. The trick is figuring out
> if NDS spokes going slack is more likely to be an issue than DS spokes
> getting overloaded by torque. Unless you are sprinting up steep hills
> *in a low gear* the torque isn't going to be a problem with only half
> the spokes crossed. So... I still think radial on the NDS would be my
> choice.
Looking at my ****ny new 7800 rear hub, I can't imagine it is anything
but torsionally stiff. Any flex it would show under load would have to
be microscopic.
If that is the case, it doesn't matter which side the spokes are on.
Any "pull" spoke transfers torque to the rim, whichever side it is on.
So then it would make sense to have radial on the DS, not the NDS.
That way the shorter spoke and resulting angle helps make up for the
more inboard placement of the DS flange.
This is totally unscientific and anecdotal, but I just took my light
wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short
test, and did some purposefully agressive side to side sprints. It
seems the wheel only have the occasional flop when I lean the bike to
the right, and the rims feels like it flexes in toward the NDS. The
flanges mean there is essentially no dish, so the only real difference
between each side is spoke length and thus angle. The rim does not
seem to flop toward the DS. That makes sense because the NDS is radial
and is in better position to resist.
Joseph
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