1" carbon steerer flexible?

They are definitely on the way out

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

Quoted message said:

Subject: Re: 1" carbon steerer flexible? From: "ari" [email hidden] Date: 8/4/03 11:07 AM Pacific
Daylight Time Message-id: <[email hidden]>

They are definitely on the way out

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

They may be on their way out due to marketing, but that doesn't answer the question. Try a
google search for articles on 1" forks. I don't think very many bikes are being made for 1"
steerers anymore.

Josh Zlotlow [email hidden] Sacramento, California Sacramento Golden Wheelmen www.sacgw.com

"ari" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

They are definitely on the way out

This does not address the question.

Quoted message said:

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

"Nick Burns" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

"ari" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

They are definitely on the way out

This does not address the question.

So what, its my two cents. Buy a 1" headset and then you have to deal with sourcing 1" headsets and
1-1/8" stems with those hack shims. Furthermore, manufacturers specify a shorter maximum stack
height on 1" carbon steerer tubes than they do with 1-1/8". So good luck with the colnago (not sure
who else still makes new frames with 1" head tubes) and we'll see you back here in a 3-5 years when
you need that link to sheldon brown's site with hard to find parts.

Quoted message said:

Quoted message said:

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go

for.

Quoted message said:

Quoted message said:

Quoted message said:

A friend who previously had one said to avoid 1 inch carbon steerers because they are
flexible. Is there any truth to this?

Thanks, Wayne

"ari" <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

So good luck with the colnago (not sure who else still makes new frames with 1" head tubes)

Mark Hickey does. habcycles.comtechstuf.htmlOpen ↗

-- Wayne Menzie

Wayne Menzie <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

"ari" <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

So good luck with the colnago (not sure who else still makes new frames with 1" head tubes)

Mark Hickey does. habcycles.comtechstuf.htmlOpen ↗

So does Surly. surlybikes.comsteamrollerSPEC.htmOpen ↗

--
Wayne Menzie

1" carbon steerers are definitely not recommended for larger riders who are hard on equipment. You
can draw your own conclusions.

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

"Wayne Menzie" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

"ari" <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

So good luck with the colnago (not sure who else still makes new frames with 1" head tubes)

Mark Hickey does. habcycles.comtechstuf.htmlOpen ↗

mark conveniently takes a "weight doesn't matter" approach when it comes to his straight guage
tubing, and then becomes a weight weenie when describing the merits of the one inch steerer tube.
Hey if you all want one inch steerer tubes, suit yourselves, but don't pretend like its some
superior retro technology that will make your life easier (like friction shifting).

Quoted message said:

-- Wayne Menzie

"ari" <[email hidden]> wrote in :"]news:[email hidden]:

Quoted message said:

mark conveniently takes a "weight doesn't matter" approach when it comes to his straight
guage tubing

That's not the way I read his page. I believe his exact words are "Double butting and tapering of
titanium tubing are both very difficult and expensive processes". Considering that he uses 0.9mm
wall Ti tubing, I'm not sure that you'd actually save that much weight by going to a butted tube. It
seems like he just saw a way to cut some significant costs on Ti frames without severly affecting
performance.

Quoted message said:

and then becomes a weight weenie when describing the merits of the one inch steerer tube.

Again, I think you misread what he wrote. As I understand it, the rationale behind going to a 1 1/8"
steerer tube is that you can use less material and make it just as strong. In other words, the
weight weenies are the ones arguing for the 1 1/8" steerer. He appears to be pointing out that the
perceived weight savings disappear under closer scrutiny.

Quoted message said:

Hey if you all want one inch steerer tubes, suit yourselves, but don't pretend like its some
superior retro technology that will make your life easier (like friction shifting).

Man, you must have me confused with someone else. I was just helping you out when you said you're
"not sure who else still makes new frames with 1" head tubes."

--
Wayne Menzie

"ari" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

So good luck with the colnago (not sure who else still makes new frames with 1" head tubes)

Cervelo (and they've basically said that they'll go to 1.125" over their dead bodies). Javelin

Quoted message said:

and we'll see you back here in a 3-5 years when you need that link to sheldon brown's site
with hard

to

Quoted message said:

find parts.

Since the trend is also to integrated headsets, I'm not sure what part will be hard to find...the
bearings may eventually wear out, but I believe that they are a standard industrial size.

Andy Coggan

wpein-<< I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there any
truth to this? >><BR><BR>

Balderdash...1 inch carbon steerers have been around for years..1 1/8 inch was an answer not to
flexibility but cost decrease, mostly on the frameset.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

ari-<< They are definitely on the way out >><BR><BR>

Really, Reynolds says they make more 1 inch than 1 1/8 inch...

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

Actually, the steerer is one area of the bike where a little flexibility is good. Without some
flexibility of the steerer, the fork will ride harshly. There is quite a difference in the ride of
various carbon forks, and stiffness of the steerer is one reason why.

Todd Kuzma Heron Bicycles LaSalle, Il 815-223-1776 heronbicycles.comheronbicycles.comOpen ↗

In 2002 Kelme used the Look KG386 frame in the Tour de France. And probably for the entire season.
It has a 1" steerer all carbon fork. Since it is a monocoque frame, Look is not able to make custom
frames for the racers with 1.125" head tubes for this model. And of course all of the teams
sponsored by Colnago use the Star 1" steerer all carbon fork. I would guess Cycling News would have
had articles about all of the fork problems if there were any.

Flex in forks is similar to flex in frames. All of a sudden everyone is concerned about it. Thinking
its some evil problem that will cause you to crash and die every time you ride your bike. Or worse,
cause you to lose 1/100th of a second while climbing a mountain pass. Long, long ago racers somehow
managed to ride all of the big races using Vitus or Alan aluminum and carbon frames, or TVT carbon
frames. I recall someone riding a Bottechia carbon tubed frame in the 1989 Tour de France and
somehow managing to win it. But maybe he would have won by 9 seconds if he had a stiff frame and
stiff fork.

Flex in carbon fork steerers comes from two places. 1. A short head tube with the headset bearings
close together, obviously, does not provide as much support as a long head tube with the bearings
spaced far apart. Shimano rear hubs have an advantage over other models due to the bearings being
farther apart and giving more support to the axle. And Shimano is carrying this bearing spacing
concept even further with their new XTR and Dura Ace cranks with the bearings outside of the bottom
bracket shell. 2. Unsupported steerer above the top headset bearings. If you put lots of spacers
below the stem, you will have lots of steerer that is only supported at one end by the top headset
bearing. The closer you get the stem to the top headset bearing, the less steerer you have
unsupported. And the less flex in the steerer you will have. If you have 3" of spacers below the
stem and the stem has a 2" long clamp, you have 5' of unsupported steerer and a 5" long lever to
work against the top headset bearings. If you have the stem right on top of the top headset
bearings, you have only 2" of unsupported steerer and a 2" lever to work against the bearings. You
can move things easier with a longer lever. And longer levers will flex more than shorter levers.

So flex in fork steerers really has to do with how long your head tube is and how many spacers you
have between the stem and top headset bearing. Diameter of the fork steerer is immaterial.

However, if I had a choice on which size fork to have on a new bicycle, I would choose the 1.125"
size. And since you are asking the question about whether 1" is flexible, you must have some doubts
in your mind. Just pick the 1.125" size and then you won't have to worry if your new frame and fork
has a flexible steerer.

Wayne Pein <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

Doug said:

1" carbon steerers are definitely not recommended for larger riders who are hard on equipment. You
can draw your own conclusions.

My Santana TANDEM has a 1" steer tube. That bike puts stresses on the steer tube a 300 pound gorilla
on a single couldn't dream of - and I'm still sportin' all my front teeth.

It's all just a matter of designing in the right margin of safety. In the case of my tandem's fork,
it is a VERY thick steel steer tube.

In the case of manufacturers of 1" and 1-1/8" CF steer tube forks, it's kind of hard to imagine
they use a different ultimate strength factor between the two sizes. The diameter is close enough
it's simply a matter of using a bit thicker material in the 1" steer tube to get the same
ultimate strength.

There IS another school of thought about flex in steer tubes as well. First, it's hardly a big
problem for most of us. Beyond that, if you make the steer tube absolutely stiff, ALL the flex
occurs at the steer tube/crown junction. This means that, like butted spokes, sometimes stiffer may
not be better.

In the end, it's probably a moot point because most of the fork manufacturers are over-engineering
their products. Or at least we all HOPE so!!!

Mark Hickey Habanero Cycles habcycles.comhabcycles.comOpen ↗ Home of the $695 ti frame

Actually, I think the real reason they started 1 1/8" steerer tubes was to try and put a little more
bearing surface into mountain bikes which were particularly hard on the lower bearings ... larger
diameter headset, more balls to take/spread the load and avoid brinneling (sp?) the races. (Seems to
me Klein was putting in an aircraft bearing in a humongous headset for that reason.)

I don't think the larger steerers were ever developed for improvements in stiffness, strength or
opportunity to save weight. I think the trend was built upon the desire to increase the size of
the headset.

Given all that, I rather like my 1" steerer tube with its quill design, painted to match,
Ibis Ti stem.

R / John

(Russell Seaton) said:

Flex in forks is similar to flex in frames. All of a sudden everyone is concerned about it.
Thinking its some evil problem that will cause you to crash and die every time you ride your bike.

Having laid waste (without crashing) to too many 1" forks to count, I can assure you that it is an
issue for some riders. Degree of flex is a factor in failure rate, like material tensile strength or
number of stress cycles. It also has a huge effect on shudder and deflection under braking as well
as "speed wobble".

Quoted message said:

Flex in carbon fork steerers comes from two places. 1. A short head tube with the headset bearings
close together, obviously, does not provide as much support as a long head tube with the bearings
spaced far apart.

But the flex you identify here is in the bearings themselves. The shorter the steerer, the stiffer
it is (inversely proportional to the cube of length). A long steerer such as I use-- up to 380mm--
flexes quite a lot along its length even though it is well supported by its bearings.

An extreme example: My tallbike has a 1" steel steerer tube with a 5mm wall thickness, running
inside a head tube with a 35mm ID (a little larger than a 1 1/8" head tube). This seems like a
recipe for great stiffness. But because the steerer is 950mm long, it flexes enough to clank the
inside of the head tube over bumps. Note that this steerer is about 3 times stiffer than the
stiffest 1" steerers generally available, for any given length!

My strong impression is that fork flex becomes more, not less, as the steerer gets longer.

Quoted message said:

2. Unsupported steerer above the top headset bearings. If you put lots of spacers below the stem,
you will have lots of steerer that is only supported at one end by the top headset bearing. The
closer you get the stem to the top headset bearing, the less steerer you have unsupported. And
the less flex in the steerer you will have.

...

Quoted message said:

And longer levers will flex more than shorter levers.

The long lever in almost every case is the fork. Its effect on steerer tube flex, both because
of the size of the loads applied and the lever arm length, dwarfs the effect of anything above
the headset.

Quoted message said:

So flex in fork steerers really has to do with how long your head tube is and how many spacers you
have between the stem and top headset bearing. Diameter of the fork steerer is immaterial.

Yes, but opposite of what you propose; no; and no.

Quoted message said:

Just pick the 1.125" size and then you won't have to worry if your new frame and fork has a
flexible steerer.

Also incorrect. For instance an aluminum steerer, common in 1 1/8" diameter, would have to be 1.4"
to match the stiffness of a 1" steel steerer in the same wall thickness. Carbon's stiffness is a
product of the amount and density of fibers and their directional orientation. Either a carbon or an
aluminum steerer in 1.125" is likely to be much less stiff than a 1" steel steerer.

The principal factors that apply to steerer tube stiffness, in diminishing order of magnitude, are
as follows:

1) material type
2) steerer wall thickness, because it can vary greatly
3) steerer diameter, because it cannot vary by much in most bike types

Other factors such as steerer length are of a much smaller magnitude within typical parameters.

Chalo Colina

"Wayne Pein" <[email hidden]> wrote in message "]news:[email hidden]...

Quoted message said:

I'm thinking about a new bike and what fork and steerer I might go for. A friend who
previously had one said to avoid 1 inch carbon steerers because they are flexible. Is there
any truth to this?

Thanks, Wayne

Before you go with a 1" carbon steerer, be sure to think about how much extension you will need
above the top of the headset. In my experience I have had no issue with 1" carbon steerers, but I
don't tend to have much extension above the top of the headset.

However, I have had friends who have experienced "flexy" conditions when standing or pulling on the
bars to a degree that it scared them. It may have just been the strange sensation, but that can be
important.