Spoke Tension of Radial/3x rear wheel

[Qui Si Parla Ca]

cleo-<< but half radial rear wheels are substantially more
durable than conventional ones. >><BR><BR>

In my experience of building lots of wheels, for all sizes
of riders, including loaded touring and tandems, this just
isn't true when compared to a well made, with apporopriate
components to the situation, and lacing 3 cross on ther
rear, left side.

I have never built a weheel using radial left side, my
wheels don't break spokes.

Like british threaded BBs, this is a result of wheels that
are not built prtoperly, that is, with not enough tension on
the right side rear.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St.
Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali
costruite eccezionalmente bene"

 

[Chalo]

daveornee <[email protected]> wrote:

> Would there be any durability benefit of having tangential
> spoking on the left side with all the heads pointing out?

In principle, yes. Also, lacing drive side spokes all heads-
in increases the bracing angle on that side. The trouble
lies in determining a lacing pattern that does not leave
some spokes deflecting outwards at the elbow and bending
harshly over the adjacent crossing spoke. There is also the
potential for interference between the inner sprocket or
freewheel body and the spokes, since the net spoke line gets
shifted 3mm or more to the right.

Winkel Wheels has made a reputation for building wheels all
heads-in, which they call "Race Lace". They way they do it,
as I understand, simply increases the bracing angle on both
sides, rather than reducing net offset.

Spoke lengths can be mixed (e.g. x2/x4) to allow adjacent
spokes to lie neatly alongside one another, but this means
that the shorter spokes must be tensioned much tighter than
the longer ones. To me, that does not seem like a good idea,
but I am open to further illumination on the matter.

Shimano made some hubs in the '80s that had grooved flanges
to allow all heads-in lacing.

http://www.classicrendezvous.com/Japan/Shim_AX_hubs.htm

> I don't have a statistical basis for saying that they
> aren't as durable except for the fact that I have never
> seen a broken left rear flange except for a half radial
> spoked rear wheel.

Yes, that seems to be a chronic failure mode for radially
laced wheels. I expect that such failures would be rare if
hubs were designed to be radially laced, but it appears most
hubs are not. Having lost a couple of otherwise very nice
wheels that way, at this point I would not use radial lacing
on any hub whose manufacturer recommends against it.

Chalo Colina

 

[daveornee]

Originally posted by Chalo
daveornee <[email protected]> wrote:

> Would there be any durability benefit of having tangential
> spoking on the left side with all the heads pointing out?

In principle, yes. Also, lacing drive side spokes all heads-
in increases the bracing angle on that side. The trouble
lies in determining a lacing pattern that does not leave
some spokes deflecting outwards at the elbow and bending
harshly over the adjacent crossing spoke. There is also the
potential for interference between the inner sprocket or
freewheel body and the spokes, since the net spoke line gets
shifted 3mm or more to the right.

Winkel Wheels has made a reputation for building wheels all
heads-in, which they call "Race Lace". They way they do it,
as I understand, simply increases the bracing angle on both
sides, rather than reducing net offset.

Spoke lengths can be mixed (e.g. x2/x4) to allow adjacent
spokes to lie neatly alongside one another, but this means
that the shorter spokes must be tensioned much tighter than
the longer ones. To me, that does not seem like a good idea,
but I am open to further illumination on the matter.

Shimano made some hubs in the '80s that had grooved flanges
to allow all heads-in lacing.

http://www.classicrendezvous.com/Japan/Shim_AX_hubs.htm

> I don't have a statistical basis for saying that they
> aren't as durable except for the fact that I have never
> seen a broken left rear flange except for a half radial
> spoked rear wheel.

Yes, that seems to be a chronic failure mode for radially
laced wheels. I expect that such failures would be rare if
hubs were designed to be radially laced, but it appears most
hubs are not. Having lost a couple of otherwise very nice
wheels that way, at this point I would not use radial lacing
on any hub whose manufacturer recommends against it.

Chalo Colina

I to am open to more illumination on the matter.
However, until I am convinced otherwise... and see something from suitable hub manufacturers (Campy, Shimano, Phil Wood as examples) I will not be building any wheels with radial spoking.
I re-read the chapter in Barnetts on the subject and came away with similar conclusions.
The interpretation I have on my score card says 4 (Chalo, Brandt, Barnett, anc Chisholm) wise statements against radial spoking. There certainly are well reasoned arguments on both sides, but not sifficient to change the way I plan to build wheels.
I am also keeping my 7 speed 135 mm OLD mountain bicycle wheels (Phil Wood FW and XT Cassette) and continue to use 160 mm OLD on our tandems and 135 mm OLD on my loaded touring bicycle.

 

[Mark South]

"Chalo" <[email protected]> wrote in message
news:[email protected]...
> I expect that such failures would be rare if hubs were
> designed to be radially laced, but it appears most hubs
> are not.

The 2004 Shimano catalogue states in the entries for several
of the hubs that they are designed to cope with radial
lacing. These are all front hubs.

 

[Cleophus]

I just wanted to jump in and say THANKS to all for your input! The info you've provided has been _very_ illuminating.

I'm new here, and am very impressed with the knowledge -- and generosity to share that knowledge -- I've seen here.

(PS: Do Sheldon Brown and Jobst Brandt really post here? It would be interesting to see their take on the half-radial issue and the discussion above.)