Radial on DS!?

[Luke Forward]

Radial on DS works? It seems against the drive-torgue theory.

My understading is that to transmit drive torgue, the rear hub DS must
at least be X2 laced,
the NDS is free to be laced radial to X4.

Powertap hub is unigue having its DS on the left. The manufacturer
says the left(DS) must be laced X3. This makes sence to me.

Shockingly, Robert Torre claimed "A properly built half radial rear
wheel will be radially laced on the drive side. It would also be best
to lace the drive side so the spoke heads are on the inside of the
flange." http://www.geocities.com/spokeanwheel/lacingsr.htm#hr

Shimano wheelsets have a unique radial-DS design which seems to be
discontined from the change of Dura Ace 7850. see
http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20/Shimano_Dura-Ace_WH-7850-SL_rear_hub

So does it mean that Shimano think Radial-DS fails?

Dear builders have you ever build a Radial-DS that works?

[Michael Johnson]

Luke Forward wrote:
> Radial on DS works? It seems against the drive-torgue theory.
>
> My understading is that to transmit drive torgue, the rear hub DS must
> at least be X2 laced,
> the NDS is free to be laced radial to X4.
>
> Powertap hub is unigue having its DS on the left. The manufacturer
> says the left(DS) must be laced X3. This makes sence to me.
>
> Shockingly, Robert Torre claimed "A properly built half radial rear
> wheel will be radially laced on the drive side. It would also be best
> to lace the drive side so the spoke heads are on the inside of the
> flange." http://www.geocities.com/spokeanwheel/lacingsr.htm#hr
>
> Shimano wheelsets have a unique radial-DS design which seems to be
> discontined from the change of Dura Ace 7850. see
> http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20/Shimano_Dura-Ace_WH-7850-SL_rear_hub
>
> So does it mean that Shimano think Radial-DS fails?
>
> Dear builders have you ever build a Radial-DS that works?

I have a set of WH-7801-SL wheels, which are Radial-DS, and they've been
absolutely bullet-proof. Robert also points out that the drive torque
will be transmitted through the hub shell with negligible twisting, so
there's no reason not to put the drive spokes on the non-drive side. The
reason for building a Radial-DS wheel is to try to balance the spoke
tensions. However, Robert also states that a 2x/3x with 3x on the drive
side is better than a Radial-DS wheel. He gives some convincing reasons
for his point of view.

I suspect that Shimano's motivation in building a 2x/2x wheel was
probably mainly cost reduction. However, they might also have been
trying to increase wheel life by spreading the drive loads across twice
as many spokes and, consequently, more evenly around the rim.

Mike Johnson

[jim beam]

Luke Forward wrote:
> Radial on DS works? It seems against the drive-torgue theory.
>
> My understading is that to transmit drive torgue, the rear hub DS must
> at least be X2 laced,
> the NDS is free to be laced radial to X4.
>
> Powertap hub is unigue having its DS on the left. The manufacturer
> says the left(DS) must be laced X3. This makes sence to me.
>
> Shockingly, Robert Torre claimed "A properly built half radial rear
> wheel will be radially laced on the drive side. It would also be best
> to lace the drive side so the spoke heads are on the inside of the
> flange." http://www.geocities.com/spokeanwheel/lacingsr.htm#hr
>
> Shimano wheelsets have a unique radial-DS design which seems to be
> discontined from the change of Dura Ace 7850. see
> http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20/Shimano_Dura-Ace_WH-7850-SL_rear_hub
>
> So does it mean that Shimano think Radial-DS fails?
>
> Dear builders have you ever build a Radial-DS that works?

oh goody, a fudster trolling with underinformed crap he hasn't bothered
to analyze for himself.

in the old days when rear hubs had skinny little bodies that could
conceivably suffer a little wind-up, radial drive side might have been
an issue. but if we bother to look, all the hubs that now use radial
drive side, all have honking great highly wind-up resistant hub bodies.
thus, there is no problem.

and there's more: to some extent, radial drive side allows a slightly
better drive side spoke bracing angle. and given that non-drive side
spokes are slacker, their tension increase from torque loading has a
[theoretically beneficial] lower starting point from a fatigue perspective.

conclusion:
we can all now safely back to bed safe in the knowledge that, as usual,
the people that have built multi-million dollar global industries not
falling on the sword of their technical incompetence might, just
conceivably, have bothered to do their homework. it's a shame that
others who comment so vocally have no financial interest in getting
their facts straight. if anything, quite the opposite.

[Ron Ruff]

On Jan 11, 2:38*am, Luke Forward <lukefow...@gmail.com> wrote:
> Radial on DS works? It seems against the drive-torgue theory.

If the hub shell is beefy enough, it does a fine job of transmitting
torque to the NDS.

> Powertap hub is unigue having its DS on the left. The manufacturer
> says the left(DS) must be laced X3. This makes sence to me.

The DS is the side that the cogs are on. The PT hub body is quite
beefy and large diameter... you can cross spokes on either side and it
will work fine. The manufacturer seems to be confused about this
however.

> Shockingly, Robert Torre claimed "A properly built half radial rear
> wheel will be radially laced on the drive side. It would also be best
> to lace the drive side so the spoke heads are on the inside of the
> flange." *http://www.geocities.com/spokeanwheel/lacingsr.htm#hr

Try that and guess how long the flange will last. Also having spokes
with heads in on the DS will increase the bracing angle and improve
the tension balance, but the flange is *already* as far over as
possible to keep the derailleur from hitting the spokes. If you have
extra clearance then maybe you could get away with it. Another issue
is that using only the NDS spokes (which have low tension to start
with) for torque transmission increases the chance that they will go
slack from combined torque and radial/lateral loads. Robert Torre has
a big website, but you should not believe most of what is on it...

> So does it mean that Shimano think Radial-DS fails?

Mavic has been doing this for many years, mostly because their fat
aluminum spokes would require too much dish if they were crossed on
the DS. If the wheel is properly designed it works fine. I don't think
it is a good idea on hubs that aren't designed for it though.

[jobst.brandt@stanfordalumni.org]

Look Backward writes:

> Radial on DS works? It seems against the drive-torgue theory.

> My understading is that to transmit drive torgue, the rear hub DS
> must at least be X2 laced, the NDS is free to be laced radial to X4.

> Powertap hub is unigue having its DS on the left. The manufacturer
> says the left(DS) must be laced X3. This makes sence to me.

> Shockingly, Robert Torre claimed "A properly built half radial rear
> wheel will be radially laced on the drive side. It would also be
> best to lace the drive side so the spoke heads are on the inside of
> the flange."

http://www.geocities.com/spokeanwheel/lacingsr.htm#hr

> Shimano wheelsets have a unique radial-DS design which seems to be
> discontined from the change of Dura Ace 7850. see

http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20/Shimano_Dura-Ace_WH-7850-SL_rear_hub

> So does it mean that Shimano think Radial-DS fails?

> Dear builders have you ever build a Radial-DS that works?

Just because someone does it and it appears to work doesn't mean it is
good or even better than conventional design. Just to prove that, one
of the guys at the bicycle shop spokes a standard low flange
Campagnolo hub radially on both sides and allowed people to ride it so
they could discover that torque wind-up is imperceptible. In the long
run this will tear the flange apart as has been show even by 3x
spoking when the hub was re-spoked with opposite spoke orientation.

Jobst Brandt

[Zog The Undeniable]

Luke Forward wrote:
> Radial on DS works? It seems against the drive-torgue theory.
>
> My understading is that to transmit drive torgue, the rear hub DS must
> at least be X2 laced,
> the NDS is free to be laced radial to X4.
>
> Powertap hub is unigue having its DS on the left. The manufacturer
> says the left(DS) must be laced X3. This makes sence to me.
>
> Shockingly, Robert Torre claimed "A properly built half radial rear
> wheel will be radially laced on the drive side. It would also be best
> to lace the drive side so the spoke heads are on the inside of the
> flange." http://www.geocities.com/spokeanwheel/lacingsr.htm#hr
>
> Shimano wheelsets have a unique radial-DS design which seems to be
> discontined from the change of Dura Ace 7850. see
> http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20/Shimano_Dura-Ace_WH-7850-SL_rear_hub
>
> So does it mean that Shimano think Radial-DS fails?
>
> Dear builders have you ever build a Radial-DS that works?

It's been done for years. You just have to ensure the hub shell can
take it.

BMX bikes with small wheels and 48 spokes, and low-riders with 144
spokes, often have completely radial rear wheels, spoke wind-up being
less of a problem in these cases.

[David L. Johnson]

Michael Johnson wrote:

>> Powertap hub is unigue having its DS on the left. The manufacturer
>> says the left(DS) must be laced X3. This makes sence to me.

Well, it doesn't to me. How can the drive side be on the left? The
chain is where?
>>
>> Shockingly, Robert Torre claimed "A properly built half radial rear
>> wheel will be radially laced on the drive side. It would also be best
>> to lace the drive side so the spoke heads are on the inside of the
>> flange." http://www.geocities.com/spokeanwheel/lacingsr.htm#hr

That would be rather shocking. Not only does it require a hub with a
stronger (and heavier) shell, but putting heads in moves the spokes out
closer to the chain. Infinitesimally that will improve the bracing
angle, but at the cost of, well, the spokes being closer to the chain.

>> So does it mean that Shimano think Radial-DS fails?

What makes you think they think it "fails"? It's all just marketing,
anyway. They need to change the design every season, or no one will buy
their wheels just because their old ones are out of fashion. Can't have
that.

> I have a set of WH-7801-SL wheels, which are Radial-DS, and they've been
> absolutely bullet-proof. Robert also points out that the drive torque
> will be transmitted through the hub shell with negligible twisting,

It better be negligible. But a standard hub shell is not able to
prevent such twisting.

> there's no reason not to put the drive spokes on the non-drive side. The
> reason for building a Radial-DS wheel is to try to balance the spoke
> tensions.

You might try to balance the spoke tension that way, but you would fail.

> I suspect that Shimano's motivation in building a 2x/2x wheel was
> probably mainly cost reduction. However, they might also have been
> trying to increase wheel life by spreading the drive loads across twice
> as many spokes and, consequently, more evenly around the rim.

Huh?

--

David L. Johnson

As far as the laws of mathematics refer to reality, they are not
certain, and as far as they are certain, they do not refer to reality.
-- Albert Einstein

[steve]

On Jan 11, 9:08*am, jim beam <spamvor...@bad.example.net> wrote:
> Luke Forward wrote:
> > Radial on DS works? It seems against the drive-torgue theory.
>
> > My understading is that to transmit drive torgue, the rear hub DS must
> > at least be X2 laced,
> > the NDS is free to be laced radial to X4.
>
> > Powertap hub is unigue having its DS on the left. The manufacturer
> > says the left(DS) must be laced X3. This makes sence to me.
>
> > Shockingly, Robert Torre claimed "A properly built half radial rear
> > wheel will be radially laced on the drive side. It would also be best
> > to lace the drive side so the spoke heads are on the inside of the
> > flange." *http://www.geocities.com/spokeanwheel/lacingsr.htm#hr
>
> > Shimano wheelsets have a unique radial-DS design which seems to be
> > discontined from the change of Dura Ace 7850. see
> >http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20....
>
> > So does it mean that Shimano think Radial-DS fails?
>
> > Dear builders have you ever build a Radial-DS that works?
>
> oh goody, a fudster trolling with underinformed crap he hasn't bothered
> to analyze for himself.
>
> in the old days when rear hubs had skinny little bodies that could
> conceivably suffer a little wind-up, radial drive side might have been
> an issue. *but if we bother to look, all the hubs that now use radial
> drive side, all have honking great highly wind-up resistant hub bodies.
> * thus, there is no problem.
>
> and there's more: to some extent, radial drive side allows a slightly
> better drive side spoke bracing angle. *and given that non-drive side
> spokes are slacker, their tension increase from torque loading has a
> [theoretically beneficial] lower starting point from a fatigue perspective..
>
> conclusion:
> we can all now safely back to bed safe in the knowledge that, as usual,
> the people that have built multi-million dollar global industries not
> falling on the sword of their technical incompetence might, just
> conceivably, have bothered to do their homework. *it's a shame that
> others who comment so vocally have no financial interest in getting
> their facts straight. *if anything, quite the opposite.- Hide quoted text -
>
> - Show quoted text -

If shimano did there homework on their wheels why did they switch from
radial drive back to a more traditional cross drive side? My only
guess is that they could make the hub significantly lighter, but the
tension will not be as even and wheel stiffness will decrease
slightly.

Steve Sauter

[Luke Forward]

On Jan 12, 12:13*am, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On Jan 11, 2:38*am, Luke Forward <lukefow...@gmail.com> wrote:
> > Powertap hub is unigue having its DS on the left. The manufacturer
> > says the left(DS) must be laced X3. This makes sence to me.
>
> The DS is the side that the cogs are on. The PT hub body is quite
> beefy and large diameter... you can cross spokes on either side and it
> will work fine. The manufacturer seems to be confused about this
> however.

I've read the manual of Powertap hub in which it has a cutaway
picture, the hub structure does have a driveside on its left(no cogs).
Ligero built it leftside X3 rightside X1. see
http://www.flickr.com/photos/ligerowheels/577544451/in/set-72157600523553677/

[Ron Ruff]

On Jan 11, 9:42*am, Luke Forward <lukefow...@gmail.com> wrote:
> I've read the manual of Powertap hub in which it has a cutaway
> picture, the hub structure does have a driveside on its left(no cogs).

I know how the hub works... but there is no practical reason to
designate the left side as the drive side.

[Ben C]

On 2008-01-11, David L. Johnson <david.johnson@lehigh.edu> wrote:
> Michael Johnson wrote:
>
>>> Powertap hub is unigue having its DS on the left. The manufacturer
>>> says the left(DS) must be laced X3. This makes sence to me.
>
> Well, it doesn't to me. How can the drive side be on the left? The
> chain is where?

I suppose the chain could be on the right, but the pawls that actually
engage the hub could be over on the left.

[Ozark Bicycle]

On Jan 11, 12:52*pm, steve <ssau...@emich.edu> wrote:
> On Jan 11, 9:08*am, jim beam <spamvor...@bad.example.net> wrote:
>
>
>
> > Luke Forward wrote:
> > > Radial on DS works? It seems against the drive-torgue theory.
>
> > > My understading is that to transmit drive torgue, the rear hub DS must
> > > at least be X2 laced,
> > > the NDS is free to be laced radial to X4.
>
> > > Powertap hub is unigue having its DS on the left. The manufacturer
> > > says the left(DS) must be laced X3. This makes sence to me.
>
> > > Shockingly, Robert Torre claimed "A properly built half radial rear
> > > wheel will be radially laced on the drive side. It would also be best
> > > to lace the drive side so the spoke heads are on the inside of the
> > > flange." *http://www.geocities.com/spokeanwheel/lacingsr.htm#hr
>
> > > Shimano wheelsets have a unique radial-DS design which seems to be
> > > discontined from the change of Dura Ace 7850. see
> > >http://www.cyclingnews.com/photos.php?id=/photos/2007/tech/news/08-20....
>
> > > So does it mean that Shimano think Radial-DS fails?
>
> > > Dear builders have you ever build a Radial-DS that works?
>
> > oh goody, a fudster trolling with underinformed crap he hasn't bothered
> > to analyze for himself.
>
> > in the old days when rear hubs had skinny little bodies that could
> > conceivably suffer a little wind-up, radial drive side might have been
> > an issue. *but if we bother to look, all the hubs that now use radial
> > drive side, all have honking great highly wind-up resistant hub bodies.
> > * thus, there is no problem.
>
> > and there's more: to some extent, radial drive side allows a slightly
> > better drive side spoke bracing angle. *and given that non-drive side
> > spokes are slacker, their tension increase from torque loading has a
> > [theoretically beneficial] lower starting point from a fatigue perspective.
>
> > conclusion:
> > we can all now safely back to bed safe in the knowledge that, as usual,
> > the people that have built multi-million dollar global industries not
> > falling on the sword of their technical incompetence might, just
> > conceivably, have bothered to do their homework. *it's a shame that
> > others who comment so vocally have no financial interest in getting
> > their facts straight. *if anything, quite the opposite.- Hide quoted text -
>
> > - Show quoted text -
>
> If shimano did there homework on their wheels why did they switch from
> radial drive back to a more traditional cross drive side?

Marketing might be a part of that: they want the !new! product to be
discernably different than what went before. It wouldn't surprise me a
bit to see the next generation go back to radial DS spoking.


> My only
> guess is that they could make the hub significantly lighter, but the
> tension will not be as even and wheel stiffness will decrease
> slightly.
>
> Steve Sauter

[jobst.brandt@stanfordalumni.org]

Ron Ruff writes:

>> I've read the manual of Powertap hub in which it has a cutaway
>> picture, the hub structure does have a drive side on its left(no
>> cogs).

> I know how the hub works... but there is no practical reason to
> designate the left side as the drive side.

It is the side on which drive torque enters the hub. With most hubs
the ratchet escapement is at the sprockets and therefore on the right
side. If the mechanism is on the left side, and I can't imagine why
one would do that, then the left side is the driven (drive) side.

Just the same, I find plain English of "left" and "right" sides of a
rear wheel, rather than with bicycle jargon of "DS" and "NDS", terms
that can lead to confusion.

Jobst Brandt

[Tom Sherman]

jobst.brandt@stanfordalumni.org aka Jobst Brandt wrote:
> ...
> Just the same, I find plain English of "left" and "right" sides of a
> rear wheel, rather than with bicycle jargon of "DS" and "NDS", terms
> that can lead to confusion.

The portion of the crank-arm-set on my bicycle that holds the chain
wheels is mounted on the non-non-drive-side. ;)

--
Tom Sherman - Holstein-Friesland Bovinia
"And never forget, life ultimately makes failures of all people." A. Derleth

[Ron Ruff]

On Jan 11, 5:42*pm, jobst.bra...@stanfordalumni.org wrote:
> It is the side on which drive torque enters the hub. *With most hubs
> the ratchet escapement is at the sprockets and therefore on the right
> side. *If the mechanism is on the left side, and I can't imagine why
> one would do that, then the left side is the driven (drive) side.

Powertap has their torque measuring device (probably strain gauges on
a tube) between the freehub and the left side of the hub body... the
right side of the hub body is not rigidly attached to the freehub (it
floats). So by your definition the left side is the drive side. But in
practical terms, the hub body is quite solid and either flange will
transfer torque effectively... ie no risk of failure or error in
torque measurement.

[jobst.brandt@stanfordalumni.org]

Tom Sherman writes:

>> ...
>> Just the same, I find plain English of "left" and "right" sides of a
>> rear wheel, rather than with bicycle jargon of "DS" and "NDS", terms
>> that can lead to confusion.

> The portion of the crank-arm-set on my bicycle that holds the chain
> wheels is mounted on the non-non-drive-side. ;)

Well said! Does that impact your riding before the twelve o'clock hour
on major roadways? Lying down on the job, as you do, you ought to
worry about tanker-trucks and 18-wheelers when riding in the right
hand lane very very much. Ain't jargon great!

Jobst Brandt

[jobst.brandt@stanfordalumni.org]

Ron Ruff writes:

>> It is the side on which drive torque enters the hub. Â*With most
>> hubs the ratchet escapement is at the sprockets and therefore on
>> the right side. Â*If the mechanism is on the left side, and I can't
>> imagine why one would do that, then the left side is the driven
>> (drive) side.

> Powertap has their torque measuring device (probably strain gauges
> on a tube) between the freehub and the left side of the hub body...
> the right side of the hub body is not rigidly attached to the
> freehub (it floats). So by your definition the left side is the
> drive side. But in practical terms, the hub body is quite solid and
> either flange will transfer torque effectively... ie no risk of
> failure or error in torque measurement.

From what I can see in pictures the "tube" is made of four slightly
angled beams that are loaded in bending, the rest of the hub tube
having been machined away. It seems that torque may be measured by
bending of these elements.

http://www.wheelbuilder.com/thumbnail.asp?cid=51&offset=0

Jobst Brandt

[Ron Ruff]

On Jan 12, 1:57*am, jobst.bra...@stanfordalumni.org wrote:
> From what I can see in pictures the "tube" is made of four slightly
> angled beams that are loaded in bending, the rest of the hub tube
> having been machined away. *It seems that torque may be measured by
> bending of these elements.
>
> http://www.wheelbuilder.com/thumbnail.asp?cid=51&offset=0

That is just the exterior of the hub body. The new ones are made that
way, with a carbon shell underneath that... for fashion. The tube I'm
speaking of is internal, and connects the freehub to the left side of
the hub.