Radial on DS!?

Luke Forward said:

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?

The short answer is that if properly built, for most applications the margins are big enough to allow for functional wheels to be built in a number of configurations.
That a RW needs some tangential spokes is uniformly accepted by all, although I've seen high spoke count "cruiser" bikes built with full-radial rear wheels.
Some will claim that the RW hub will twist so much under pedalling force that the DS flange MUST be tangentially laced.
Other scorns the idea of a puny human being able to substantially deform by torsion a chunky aluminum cylinder and will happily put the tangentially laced spokes anywhere they damn well wants. Heads-in, radial lacing of the DS then will give a slight improvement in spoke angle, equivalent to having the flange 1/2 of the flange thickness further out as compared to a tangentially laced flange. So if you're more concerned with spoke angle than with hub twisting then that's the choice for you.

Luke Forward said:

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

Luke Forward said:

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.

Quoted message said:

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.

Quoted message said:

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...

Quoted message said:

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.

Ron Ruff said:

Luke Forward said:

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/

Michael Johnson said:

Quoted message said:

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?

Quoted message said:

Quoted message said:

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.

Quoted message said:

Quoted message said:

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.

Quoted message said:

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.

Quoted message said:

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.

Quoted message said:

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

David L. Johnson said:

Michael Johnson said:

Quoted message said:

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.

Look Backward said:

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

Quoted message said:

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.

Quoted message said:

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.

Quoted message said:

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

Quoted message said:

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

Quoted message said:

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

Quoted message said:

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

Luke Forward said:

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.

Luke Forward said:

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.

Ron Ruff said:

Quoted message said:

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).

Quoted message said:

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

aka Jobst Brandt said:

...
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

Tom Sherman said:

Quoted message said:

...
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.

Quoted message said:

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

Quoted message said:

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.

Ron Ruff said:

Quoted message said:

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.

Quoted message said:

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

Quoted message said:

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.