Tips on carbon fiber WSD bikes?

On 1/4/2011 4:00 PM, Steve Freides wrote:

snip

I think letting 5-10 lbs. of air pressure out of whatever tire you find
to ride harshly will make them equal in comfort.

Sheldon goes into all this. There's a myth that a wider tire will have
less rolling resistance than a narrower tire, but of course that's not
true when both are inflated to the proper pressure. The narrower, higher
pressure tire will have less resistance than the wider, lower pressure
tire, but the ride will be harsher than the wider tire. Unless the rider
is a racer, going with the wider tire is preferable.

The more I see of this thread, the more I'm convinced that we're all
very slow, and that this is obviously a troll. "Plushness?!"

wrote:
James Steward wrote:

We need to have a discussion some time about stiff wheels. I'm
having trouble conceptualizing how an adequately tensioned wheel
would not be radially stiff (not talking laterally). I hear talk
from various racer buddies about how one wheel or another is
super stiff and a "secret weapon" (another over-used advertising
term) in sprints, etc., which suggests to me that a wheel can be
radially limp some how, at least relatively speaking.


http://www.sheldonbrown.com/rinard/wheel/index.htm

http://www.rouesartisanales.com/article-23159755.html

The first link is lateral stiffness. The second link does talk about
frontal/radial stiffness and makes me wonder why anyone would buy a
wheel with spoke tension so low that it would allow rim deformation
under normal load -- particularly an uber-expensive carbon wheel. --

Lateral stiffness or lateral wheel collapse is dependent on rim
lateral stiffness, something that is not guaranteed by CF rims. In the
days of yore, riders would spoke up track wheels for ultimate light
weight and end up with a pretzeled wheel at the first outing. Those
were aluminum rims.

Indeed. My old set of CXP30 wheel were (as far as I could perceive)
radially stiffer than my current Open-Pro and Ksyrium wheels.

Radial stiffness relies mainly on spokes, because they must
elastically stretch to appear flexible or soft.

Yes, I have your book.

The difference became more noticeable in cornering on roads where there
is some corrugation. The CXP30 wheels tended to skip across the road
whereas the Open-Pros and Ksyriums tend to ride the bumps a little more
softly and remain in contact with the road more.

Are you using the same tires and inflation? You can't feel spoke
elasticity so I assume you are getting tire flex.

When I made the swap from Ultegra Hubs, 28 spoke front and rear CXP30s
to 32 spoke OpenPro on Mavic hubs, same tyres, same pressure (as near as
my floor pump can be used), the OpenPro wheels _felt_ like they rode
bumps around corners with less jitter across the road.

Perhaps in bumpy corners there is a combination of lateral and radial
flex that makes the OpenPros _feel_ more compliant.

As a friendly LBS owner describes it, the Open-Pros are like wearing
slippers by comparison.

Sounds like a good sales talk!

It worked! I'm still using the front OpenPro Ceramic. Sadly the hub
wore out on the rear - after about 10 years and 100,000km.

The CXP30's were bullet proof, I guess reasonably aero, but fairly heavy.

After 10 or so years of not racing, I started again last July with the
local veteran club. I've won a few A grade road sprints on the Ksyriums
now, and for someone who was never renowned as a road sprinter, I feel
the Ksyriums are no handicap, despite the low profile rim and low spoke
count (20 in the rear).

Why do you do THAT? Low spoke count and low rim profile don't like
each other!

I didn't do "THAT", Mavic did.

I've done about 10,000km on the rear Ksyrium and not had to true it. It
seems strong enough and reliable enough for what I want. It is also
light and with bladed spokes, reasonably aero for the price I paid. I'm
a satisfied customer.

I could spend a heap more and get some Zipp 303's, but I can't justify
the expense or the fluffing around with glue and tubs.

JS.

Peter Cole wrote:

I have a couple of lugged steel, a couple of welded steel, and a couple
Cannondales. The Cannondales seem much more stable at high speeds. I'll
ride no hands at 60 kph.


Is that all?

Stability is more than just material based.

JS.

In article
,
Jay Beattie wrote:

On Jan 4, 9:39Â*am, SMS wrote:
On 1/4/2011 9:33 AM, landotter wrote:

I wouldn't demand that a road bike fit 32s, like mine does, but if it
fits 28s or 25s with fenders, it gives you options for free. Why not?

There are times of the year when 32s are really nice to be able to
install, and times when the lower rolling resistance of the narrower 23s
is desirable. 23-32 is not an unreasonable range to insist upon for a
road bike.

True. It all depends on what you want from your bike and how many
bikes you want to own. I am blessed with multiple bikes, one of which
will take 35s (cyclocross) with fenders. If I were a one bike guy, I
would buy a '70s Raleigh International and call it a day.
http://home.comcast.net/~cheg01/international.html

I still have my Raleigh International.
Had some frame work done so it has no straps.
630 wheels
28 mm slicks
DT shifters
7 speed freehub
48-38-28/12-21 gearing
rack & panniers
no mudguards.

Not my only bike, though. The RI is good in corners
only compared to other utility bikes: slack angles,
0.450 m chain stays, 1.035 m wheel base. You would find
yourself craving excitement.

--
Michael Press

On Jan 4, 4:26*pm, James wrote:
wrote:
James Steward wrote:

We need to have a discussion some time about stiff wheels. *I'm
having trouble conceptualizing how an adequately tensioned wheel
would not be radially stiff (not talking laterally). *I hear talk
from various racer buddies about how one wheel or another is
super stiff and a "secret weapon" (another over-used advertising
term) in sprints, etc., which suggests to me that a wheel can be
radially limp some how, at least relatively speaking.

http://www.sheldonbrown.com/rinard/wheel/index.htm

http://www.rouesartisanales.com/article-23159755.html

The first link is lateral stiffness. *The second link does talk about
frontal/radial stiffness and makes me wonder why anyone would buy a
wheel with spoke tension so low that it would allow rim deformation
under normal load -- particularly an uber-expensive carbon wheel. --

Lateral stiffness or lateral wheel collapse is dependent on rim
lateral stiffness, something that is not guaranteed by CF rims. *In the
days of yore, riders would spoke up track wheels for ultimate light
weight and end up with a pretzeled wheel at the first outing. *Those
were aluminum rims.

Indeed. *My old set of CXP30 wheel were (as far as I could perceive)
radially stiffer than my current Open-Pro and Ksyrium wheels.

Radial stiffness relies mainly on spokes, because they must
elastically stretch to appear flexible or soft.

Yes, I have your book.

The difference became more noticeable in cornering on roads where there
is some corrugation. *The CXP30 wheels tended to skip across the road
whereas the Open-Pros and Ksyriums tend to ride the bumps a little more
softly and remain in contact with the road more.

Are you using the same tires and inflation? *You can't feel spoke
elasticity so I assume you are getting tire flex.

When I made the swap from Ultegra Hubs, 28 spoke front and rear CXP30s
to 32 spoke OpenPro on Mavic hubs, same tyres, same pressure (as near as
my floor pump can be used), the OpenPro wheels _felt_ like they rode
bumps around corners with less jitter across the road.

You must have Princess and the Pea sensibilities. I switch between
Open Pros and Aeroheads and old MA2s and Open 4CDs and can't tell the
difference when using the same tire. All are tensioned to 100kgf or
better. The MA2 is probably running 120-130 kgf since it can twist it
up until it tacos without cracking spoke holes, plus it is an old
wheel built before I bought a tensiometer.

I guess with thread lock, you can use lower tension and actually
compress the rim without unwinding the spoke and collapsing the wheel.
I still get back to why anyone would pay serious money for a wheel
that flexes. That's just asking for fatigue failure -- particularly
with Zicral (viz., aluminum) spokes. -- Jay Beattie.

On Jan 4, 4:25*pm, SMS wrote:
On 1/4/2011 4:00 PM, Steve Freides wrote:

snip

I think letting 5-10 lbs. of air pressure out of whatever tire you find
to ride harshly will make them equal in comfort.

Sheldon goes into all this. There's a myth that a wider tire will have
less rolling resistance than a narrower tire, but of course that's not
true when both are inflated to the proper pressure. The narrower, higher
pressure tire will have less resistance than the wider, lower pressure
tire, but the ride will be harsher than the wider tire. Unless the rider
is a racer, going with the wider tire is preferable.

The more I see of this thread, the more I'm convinced that we're all
very slow, and that this is obviously a troll. "Plushness?!"

The correct term is "plushosity" -- measured with a plushometer. It is
one of the magical parameters of frame performance and usually shown
in the specs just below "liveliness." -- Jay Beattie.

On Jan 4, 3:58*pm, "Jean" wrote:
wrote in message

I realize that the final purchase decision depends largely on how well each
bike can be set up to fit me. The problem of fit is what has led me to the
WDS bikes - on the 4 (non-WSD) bikes I've owned, I've had to buy and try
multiple stems and seatposts to attempt to compensate for the overly long
top tube. On my current bike, I tried 3 different bars, 3 different stems,
and lord knows how many seatposts in order to come close to a "good" fit.

Looking at the published measurements for the mentioned bikes, they appear
to be so close that I kinda doubt there is much difference in ability their
to fit me, ride quality, "responsiveness", etc. I just wanted to know if
anyone had any experience with the mentioned bikes and could give me some
generalizations about the ride quality. (Fit, ride quality, and weight are
my main concerns.)

And to those who have responded to my post with "forget carbon fiber", well,
I want a light bike (which kinda suggests CF) and I want (versus need) a CF
bike.

Buy what you want, and be happy. Carbon fiber is a great material for
bike frames.

Have you ridden a bike with 650c wheels? There are advantages, IRT
fit, in geometry and sizing. My other half reports excellent ride
quality in spite of the smaller wheels. 23mm tires are plenty big for
her; she runs about 90psi., which is stiff enough to protect rims for
someone who rode 20mm tires front and rear and never pinch flatted
one, at 105psi and under.

I've sneaked a ride or two and, whatever the actual "numbers" are, it
doesn't steer like a slack-headtube-angle layout, common to small
frames with 700c wheels, and the saddle isn't too far forward (for
long femurs) as it would be with the usual so-called "WSD" frames that
we spec'd with sales literature, which tend to have very upright seat
tube angles.
--D-y

James Steward wrote:

We need to have a discussion some time about stiff wheels. I'm
having trouble conceptualizing how an adequately tensioned
wheel would not be radially stiff (not talking laterally). I
hear talk from various racer buddies about how one wheel or
another is super stiff and a "secret weapon" (another over-used
advertising term) in sprints, etc., which suggests to me that a
wheel can be radially limp some how, at least relatively
speaking.

http://www.sheldonbrown.com/rinard/wheel/index.htm

http://www.rouesartisanales.com/article-23159755.html

The first link is lateral stiffness. The second link does talk about
frontal/radial stiffness and makes me wonder why anyone would buy a
wheel with spoke tension so low that it would allow rim deformation
under normal load -- particularly an uber-expensive carbon wheel. --

It doesn't need to be exceptionally low because the rim distributed
spoke stiffness circumferentially if it isn't terminally radially
flexible, and fails to transfer the stiffness of spokes around the
rim.

Lateral stiffness or lateral wheel collapse is dependent on rim
lateral stiffness, something that is not guaranteed by CF rims. In the
days of yore, riders would spoke up track wheels for ultimate light
weight and end up with a pretzeled wheel at the first outing. But Those
were aluminum rims.

Indeed. My old set of CXP30 wheel were (as far as I could perceive)
radially stiffer than my current Open-Pro and Ksyrium wheels.

Radial stiffness relies mainly on spokes, because they must
elastically stretch to appear flexible or soft.

Yes, I have your book.

The difference became more noticeable in cornering on roads where there
is some corrugation. The CXP30 wheels tended to skip across the road
whereas the Open-Pros and Ksyriums tend to ride the bumps a little more
softly and remain in contact with the road more.

Are you using the same tires and inflation? You can't feel spoke
elasticity so I assume you are getting tire flex.

When I made the swap from Ultegra Hubs, 28 spoke front and rear CXP30s
to 32 spoke OpenPro on Mavic hubs, same tyres, same pressure (as near as
my floor pump can be used), the OpenPro wheels _felt_ like they rode
bumps around corners with less jitter across the road.

Perhaps in bumpy corners there is a combination of lateral and radial
flex that makes the OpenPros _feel_ more compliant.

As a friendly LBS owner describes it, the Open-Pros are like wearing
slippers by comparison.

Sounds like a good sales talk!

It worked! I'm still using the front OpenPro Ceramic. Sadly the hub
wore out on the rear - after about 10 years and 100,000km.

The CXP30's were bullet proof, I guess reasonably aero, but fairly heavy.

After 10 or so years of not racing, I started again last July with the
local veteran club. I've won a few A grade road sprints on the Ksyriums
now, and for someone who was never renowned as a road sprinter, I feel
the Ksyriums are no handicap, despite the low profile rim and low spoke
count (20 in the rear).

Why do you do THAT? Low spoke count and low rim profile don't like
each other!

I didn't do "THAT", Mavic did.

But you bought it!

I've done about 10,000km on the rear Ksyrium and not had to true it. It
seems strong enough and reliable enough for what I want. It is also
light and with bladed spokes, reasonably aero for the price I paid. I'm
a satisfied customer.

I could spend a heap more and get some Zipp 303's, but I can't justify
the expense or the fluffing around with glue and tubs.

JS.
--
Jobst Brandt

Jay Beattie wrote:

We need to have a discussion some time about stiff wheels. Â*I'm
having trouble conceptualizing how an adequately tensioned wheel
would not be radially stiff (not talking laterally). Â*I hear talk
from various racer buddies about how one wheel or another is
super stiff and a "secret weapon" (another over-used advertising
term) in sprints, etc., which suggests to me that a wheel can be
radially limp some how, at least relatively speaking:

http://www.sheldonbrown.com/rinard/wheel/index.htm

http://www.rouesartisanales.com/article-23159755.html

The first link is lateral stiffness. Â*The second link does talk
about frontal/radial stiffness and makes me wonder why anyone
would buy a wheel with spoke tension so low that it would allow
rim deformation under normal load -- particularly an
uber-expensive carbon wheel. --

Lateral stiffness or lateral wheel collapse is dependent on rim
lateral stiffness, something that is not guaranteed by CF
rims. Â*In the days of yore, riders would spoke up track wheels for
ultimate light weight and end up with a pretzeled wheel at the
first outing. Â*Those were aluminum rims.

Indeed. Â*My old set of CXP30 wheel were (as far as I could
perceive) radially stiffer than my current Open-Pro and Ksyrium
wheels.

Radial stiffness relies mainly on spokes, because they must
elastically stretch to appear flexible or soft.

Yes, I have your book.

The difference became more noticeable in cornering on roads where
there is some corrugation. Â*The CXP30 wheels tended to skip
across the road whereas the Open-Pros and Ksyriums tend to ride
the bumps a little more softly and remain in contact with the
road more.

Are you using the same tires and inflation? Â*You can't feel spoke
elasticity so I assume you are getting tire flex.

When I made the swap from Ultegra Hubs, 28 spoke front and rear
CXP30s to 32 spoke OpenPro on Mavic hubs, same tyres, same pressure
(as near as my floor pump can be used), the OpenPro wheels _felt_
like they rode bumps around corners with less jitter across the
road.

You must have Princess and the Pea sensibilities. I switch between
Open Pros and Aeroheads and old MA2s and Open 4CDs and can't tell
the difference when using the same tire. All are tensioned to
100kgf or better. The MA2 is probably running 120-130 kgf since it
can twist it up until it tacos without cracking spoke holes, plus it
is an old wheel built before I bought a tensiometer.

I guess with thread lock, you can use lower tension and actually
compress the rim without unwinding the spoke and collapsing the
wheel. I still get back to why anyone would pay serious money for a
wheel that flexes. That's just asking for fatigue failure --
particularly with Zicral (viz., aluminum) spokes.

They don't know why it flexes... and the bike shop said it was a good
wheel.
--
Jobst Brandt

wrote:
James Steward wrote:


After 10 or so years of not racing, I started again last July with the
local veteran club. I've won a few A grade road sprints on the Ksyriums
now, and for someone who was never renowned as a road sprinter, I feel
the Ksyriums are no handicap, despite the low profile rim and low spoke
count (20 in the rear).

Why do you do THAT? Low spoke count and low rim profile don't like
each other!

I didn't do "THAT", Mavic did.

But you bought it!

And I'm quite happy with it!

I've done about 10,000km on the rear Ksyrium and not had to true it. It
seems strong enough and reliable enough for what I want. It is also
light and with bladed spokes, reasonably aero for the price I paid. I'm
a satisfied customer.

I could spend a heap more and get some Zipp 303's, but I can't justify
the expense or the fluffing around with glue and tubs.

JS.