Thoughts about head tube

William O'Hara said:

I'm trying to figure this out. Is a taller head tube going
to produce better handling(combined with less rake on fork)?
I really liked the front end of my former Specialized Allez.
It seems from websites that many bikes have a short headtube.
The Allez went much better than my old motobecane in handling.
Why are so many designs of popular lines running with shortish
head tubes?

I gotta have an answer to this question. I know that a shorter
wheelbase and short chainstays are supposed to help on ascents.
Some bikes practically have the downtube joint right next to the
toptube joint. Plus, not all websites mention actual numbers for
this item. A fuji bike seems rather typical(plus the LBS has
perceived these as a good value on componentry pricing). The
head tube length is 189 mm. My old allez was in the 230 mm area.
I think this quite a different. An inch and half to me is a huge,
but I suppose others would disagree.

The Fujis from the ads appears to have very little angle in the
stem too.

Another question in my ramblings pertains to the length of the
stem. I am assuming that closest to the head tube equals more
control. Isn't this correct?

It's a non-issue. You have to start from the assumption that the bars
have to end up in the same position, no matter what the length of the
head tube.

Say you have two otherwise identical frame, one with a 12cm head tube
and one with a 13cm head tube. You set up the latter with a 12cm stem
and 1cm of spacers for the proper fit. To put the bars in the same
position on the former, you'd simply use another cm of spacers, and
the stem (and bars) would end up in precisely the same position.
Hence, there's no effect on handling one way or the other.

Other than that, the question becomes "does moving the bars up a
couple inches change the handling", and the short answer is "yes".

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

William O'Hara said:

I'm trying to figure this out. Is a taller head tube going
to produce better handling(combined with less rake on fork)?

if you mean "softer", yes. if you mean immediacy of response, no.
longer tubes, anywhere on the bike, make for a more springy frame.
obviously, you won't notice much between frames that only have a few mm
difference between the top and down tube spacings on the head tube [the
dimension that matters], but that's how the engineering principle works.

Quoted message said:

I really liked the front end of my former Specialized Allez.
It seems from websites that many bikes have a short headtube.
The Allez went much better than my old motobecane in handling.
Why are so many designs of popular lines running with shortish
head tubes?

see above. for aluminum frames, it makes for better fatigue properties too.

Quoted message said:

I gotta have an answer to this question. I know that a shorter
wheelbase and short chainstays are supposed to help on ascents.
Some bikes practically have the downtube joint right next to the
toptube joint. Plus, not all websites mention actual numbers for
this item. A fuji bike seems rather typical(plus the LBS has
perceived these as a good value on componentry pricing). The
head tube length is 189 mm. My old allez was in the 230 mm area.
I think this quite a different. An inch and half to me is a huge,
but I suppose others would disagree.

The Fujis from the ads appears to have very little angle in the
stem too.

Another question in my ramblings pertains to the length of the
stem. I am assuming that closest to the head tube equals more
control. Isn't this correct?

Quoted message said:

Say you have two otherwise identical frame, one with a 12cm head tube
and one with a 13cm head tube. You set up the latter with a 12cm stem
and 1cm of spacers for the proper fit. To put the bars in the same
position on the former, you'd simply use another cm of spacers, and
the stem (and bars) would end up in precisely the same position.
Hence, there's no effect on handling one way or the other.

Other than that, the question becomes "does moving the bars up a
couple inches change the handling", and the short answer is "yes".

What about ride quality?

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list re:
ICRR

jim beam <[email hidden]> wrote in
news:[email hidden]:

Quoted message said:

William O'Hara said:

I'm trying to figure this out. Is a taller head tube going
to produce better handling(combined with less rake on fork)?

if you mean "softer", yes. if you mean immediacy of response, no.
longer tubes, anywhere on the bike, make for a more springy frame.
obviously, you won't notice much between frames that only have a few
mm difference between the top and down tube spacings on the head tube
[the dimension that matters], but that's how the engineering principle
works.

If this is case, then why don't more bikes go in this direction?
Isn't this desired with the "comfort performance roadbikes?"

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list re: ICRR

Quoted message said:

Other than that, the question becomes "does moving the bars up a
couple inches change the handling", and the short answer is "yes".

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

I see there is a difference between your "team frame" and the
regular road frame. You used a different downtube and you have
the musucular chain stays. Why the design differences? The regular
road looks pretty good to me. I'm actually thinking that perhaps
I should get the 62 or 64 for a new bike.

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list re:
ICRR

William O'Hara said:

jim beam <[email hidden]> wrote in
news:[email hidden]:

Quoted message said:

William O'Hara said:

I'm trying to figure this out. Is a taller head tube going
to produce better handling(combined with less rake on fork)?

if you mean "softer", yes. if you mean immediacy of response, no.
longer tubes, anywhere on the bike, make for a more springy frame.
obviously, you won't notice much between frames that only have a few
mm difference between the top and down tube spacings on the head tube
[the dimension that matters], but that's how the engineering principle
works.

If this is case, then why don't more bikes go in this direction?
Isn't this desired with the "comfort performance roadbikes?"

you mean longer head tubes? because if the frame designed knows their
business, they'll know the head tube [and attendant jointing] is highly
stressed and therefore subject to substantial flex and fatigue. longer
head tubes exacerbate the problem.

William O'Hara said:

Quoted message said:

Say you have two otherwise identical frame, one with a 12cm head tube
and one with a 13cm head tube. You set up the latter with a 12cm stem
and 1cm of spacers for the proper fit. To put the bars in the same
position on the former, you'd simply use another cm of spacers, and
the stem (and bars) would end up in precisely the same position.
Hence, there's no effect on handling one way or the other.

Other than that, the question becomes "does moving the bars up a
couple inches change the handling", and the short answer is "yes".

What about ride quality?

Depends on whether it makes the bike fit better or not. It's
impossible to say otherwise, since it's an independent variable.

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

William O'Hara said:

Quoted message said:

Other than that, the question becomes "does moving the bars up a
couple inches change the handling", and the short answer is "yes".

I see there is a difference between your "team frame" and the
regular road frame. You used a different downtube and you have
the musucular chain stays. Why the design differences? The regular
road looks pretty good to me. I'm actually thinking that perhaps
I should get the 62 or 64 for a new bike.

The differences are the S-stays and the oversize oval down tube. That
provides a bit more BB stiffness and better heel-to-stay clearance
(which isn't an issue for most riders). There won't be any difference
in "ride quality" however.

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

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

Quoted message said:

William O'Hara said:

jim beam <[email hidden]> wrote in
news:[email hidden]:

Quoted message said:

William O'Hara wrote:
> I'm trying to figure this out. Is a taller head tube going
> to produce better handling(combined with less rake on fork)?
if you mean "softer", yes. if you mean immediacy of response, no.
longer tubes, anywhere on the bike, make for a more springy frame.
obviously, you won't notice much between frames that only have a few
mm difference between the top and down tube spacings on the head
tube
[the dimension that matters], but that's how the engineering
principle
works.

If this is case, then why don't more bikes go in this direction?
Isn't this desired with the "comfort performance roadbikes?"

you mean longer head tubes? because if the frame designed knows their
business, they'll know the head tube [and attendant jointing] is
highly stressed and therefore subject to substantial flex and fatigue.
longer head tubes exacerbate the problem.

I'm not so sure. A longer head tube is torsionally softer and will allow
more out of plane/lateral deflection of the frame elements but I don't
see how this translates to higher stresses/fatigue. It does however
result in a poorer handling frame when cornering.

Phil H

Phil Holman said:

Quoted message said:

Quoted message said:

>> I'm trying to figure this out. Is a taller head tube going to
>> produce better handling(combined with less rake on fork)?

Quoted message said:

Quoted message said:

Quoted message said:

> If you mean "softer", yes. If you mean immediacy of response,
> no. Longer tubes, anywhere on the bike, make for a more springy
> frame. Obviously, you won't notice much between frames that only
> have a few mm difference between the top and down tube spacings
> on the head tube [the dimension that matters], but that's how the
> engineering principle works.

Quoted message said:

Quoted message said:

Quoted message said:

If this is case, then why don't more bikes go in this direction?
Isn't this desired with the "comfort performance road bikes?"

Quoted message said:

Quoted message said:

You mean longer head tubes? Because if the frame designed knows
their business, they'll know the head tube [and attendant jointing]
is highly stressed and therefore subject to substantial flex and
fatigue. Longer head tubes exacerbate the problem.

Quoted message said:

I'm not so sure. A longer head tube is torsionally softer and will
allow more out of plane/lateral deflection of the frame elements but
I don't see how this translates to higher stresses/fatigue. It does
however result in a poorer handling frame when cornering.

I don't know where this comes from. I'm sure my bicycle frame
violates all those principles and descends as stably and sure as any,
certainly better than most of the frames of the people with whom I
descend. I'm sure you have seen the picture often enough of the
technique and it works equally well in the Alps as here or the Sierra
Nevada. This sounds like so much hypothetical imagination.

Frame flexibility occurs during pedaling, causing lateral displacement
of the BB and makes riding a straight line difficult while interfering
with rider control of the bicycle when pedaling hard. It does not
affect cornering unless pedaling, which isn't hard cornering, so it is
immaterial for cornering that has no oscillating side loads.

Jobst Brandt

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

Quoted message said:

Phil Holman said:

Quoted message said:

>>> I'm trying to figure this out. Is a taller head tube going to
>>> produce better handling(combined with less rake on fork)?

Quoted message said:

Quoted message said:

>> If you mean "softer", yes. If you mean immediacy of response,
>> no. Longer tubes, anywhere on the bike, make for a more springy
>> frame. Obviously, you won't notice much between frames that only
>> have a few mm difference between the top and down tube spacings
>> on the head tube [the dimension that matters], but that's how the
>> engineering principle works.

Quoted message said:

Quoted message said:

> If this is case, then why don't more bikes go in this direction?
> Isn't this desired with the "comfort performance road bikes?"

Quoted message said:

Quoted message said:

You mean longer head tubes? Because if the frame designed knows
their business, they'll know the head tube [and attendant jointing]
is highly stressed and therefore subject to substantial flex and
fatigue. Longer head tubes exacerbate the problem.

Quoted message said:

I'm not so sure. A longer head tube is torsionally softer and will
allow more out of plane/lateral deflection of the frame elements but
I don't see how this translates to higher stresses/fatigue. It does
however result in a poorer handling frame when cornering.

I don't know where this comes from. I'm sure my bicycle frame
violates all those principles and descends as stably and sure as any,
certainly better than most of the frames of the people with whom I
descend. I'm sure you have seen the picture often enough of the
technique and it works equally well in the Alps as here or the Sierra
Nevada. This sounds like so much hypothetical imagination.

Frame flexibility occurs during pedaling, causing lateral displacement
of the BB and makes riding a straight line difficult while interfering
with rider control of the bicycle when pedaling hard. It does not
affect cornering unless pedaling, which isn't hard cornering, so it is
immaterial for cornering that has no oscillating side loads.

Jobst Brandt

Anecdotal but, I notice poor handling when leaning the bike into a turn.
I'm sure your 6lb steel frame is well compensated for with its extra
long head tube. My experience with light weight racing frames has
resulted in my choice of a 57cm frame (I'm 6' 2"😉 which handles better
than the larger frames I've owned. I have a steel Eisentraut track frame
that is almost unrideable above 32 mph around the turns. It looks pretty
but is relegated to the indoor trainer.

Phil H

Quoted message said:

Phil Holman said:

Quoted message said:

>>> I'm trying to figure this out. Is a taller head tube going to
>>> produce better handling(combined with less rake on fork)?

Quoted message said:

Quoted message said:

>> If you mean "softer", yes. If you mean immediacy of response,
>> no. Longer tubes, anywhere on the bike, make for a more springy
>> frame. Obviously, you won't notice much between frames that only
>> have a few mm difference between the top and down tube spacings
>> on the head tube [the dimension that matters], but that's how the
>> engineering principle works.

Quoted message said:

Quoted message said:

> If this is case, then why don't more bikes go in this direction?
> Isn't this desired with the "comfort performance road bikes?"

Quoted message said:

Quoted message said:

You mean longer head tubes? Because if the frame designed knows
their business, they'll know the head tube [and attendant jointing]
is highly stressed and therefore subject to substantial flex and
fatigue. Longer head tubes exacerbate the problem.

Quoted message said:

I'm not so sure. A longer head tube is torsionally softer and will
allow more out of plane/lateral deflection of the frame elements but
I don't see how this translates to higher stresses/fatigue. It does
however result in a poorer handling frame when cornering.

I don't know where this comes from. I'm sure my bicycle frame
violates all those principles and descends as stably and sure as any,

eh? so how come you can make it "shimmy at will"? i can't make my big
tube aluminum frames shimmy at all. and guess which of us has the
inherently safer frame?

Quoted message said:

certainly better than most of the frames of the people with whom I
descend. I'm sure you have seen the picture often enough of the
technique and it works equally well in the Alps as here or the Sierra
Nevada. This sounds like so much hypothetical imagination.

Frame flexibility occurs during pedaling, causing lateral displacement
of the BB and makes riding a straight line difficult while interfering
with rider control of the bicycle when pedaling hard. It does not
affect cornering unless pedaling, which isn't hard cornering, so it is
immaterial for cornering that has no oscillating side loads.

so there's no dynamic loading on your bikes then? ever ridden with just
one hand on the bars? if yes to either question [and you'd have to be
unbelievably ignorant to say no], there are definitely side loads
regardless of pedaling.

Quoted message said:

but is relegated to the indoor trainer.

Phil H

Interesting. I have to soak this all and the previous posts in.
I went to a bigger bike for a much better fit.

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list re:
ICRR

"William O'Hara" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

but is relegated to the indoor trainer.

Phil H

Interesting. I have to soak this all and the previous posts in.
I went to a bigger bike for a much better fit.

Better fit!! I'm big on maintaining my ideal seat/BB/handle bar
configuration and I can do this with a slightly longer seat post and
stem.

For those who argue that the increase flex in these brings you right
back to where you started, the additional flex in these components does
not effect handling of the bike anything like wheels that do not track
due to a torqued frame.

I raced a carbon fiber Trek for a season and that bike was the best
handling frame I've ever ridden.

Phil H

Quoted message said:

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list
re:
ICRR

aka Jobst Brandt said:

Phil Holman said:

Quoted message said:

>>> I'm trying to figure this out. Is a taller head tube going to
>>> produce better handling(combined with less rake on fork)?

Quoted message said:

Quoted message said:

>> If you mean "softer", yes. If you mean immediacy of response,
>> no. Longer tubes, anywhere on the bike, make for a more springy
>> frame. Obviously, you won't notice much between frames that only
>> have a few mm difference between the top and down tube spacings
>> on the head tube [the dimension that matters], but that's how the
>> engineering principle works.

Quoted message said:

Quoted message said:

> If this is case, then why don't more bikes go in this direction?
> Isn't this desired with the "comfort performance road bikes?"

Quoted message said:

Quoted message said:

You mean longer head tubes? Because if the frame designed knows
their business, they'll know the head tube [and attendant jointing]
is highly stressed and therefore subject to substantial flex and
fatigue. Longer head tubes exacerbate the problem.

Quoted message said:

I'm not so sure. A longer head tube is torsionally softer and will
allow more out of plane/lateral deflection of the frame elements but
I don't see how this translates to higher stresses/fatigue. It does
however result in a poorer handling frame when cornering.

I don't know where this comes from. I'm sure my bicycle frame
violates all those principles and descends as stably and sure as any,
certainly better than most of the frames of the people with whom I
descend. I'm sure you have seen the picture often enough of the
technique...

For those who haven't"
<http://www.sheldonbrown.com/brandt/images/tiretest.jpg>.

The first time I saw this picture, my reaction was "that is a long head
tube".

--
Tom Sherman - Here, not there.

Phil Holman said:

"William O'Hara" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

but is relegated to the indoor trainer.

Phil H

Interesting. I have to soak this all and the previous posts in.
I went to a bigger bike for a much better fit.

Better fit!! I'm big on maintaining my ideal seat/BB/handle bar
configuration and I can do this with a slightly longer seat post and
stem.

For those who argue that the increase flex in these brings you right
back to where you started, the additional flex in these components does
not effect handling of the bike anything like wheels that do not track
due to a torqued frame.

I raced a carbon fiber Trek for a season and that bike was the best
handling frame I've ever ridden.

i rode one of my old steelies for the first time in months yesterday.
it was scary how much difference there was in frame torsion compared to
the aluminum frames i'd been riding. i much prefer the immediacy and
stiffness of the aluminum now and i'd never buy a steel frame again.

i've not ridden the trek, but i'd imagine the big tube diameters to
offer good torsional stiffness. is this your experience?

Quoted message said:

Phil H

Quoted message said:

--
---
William O'Hara
www.N1ey.com - Amateur Radio and Railfan Blog
www.yahoogroups.com/group/illinoiscentral - premier discussion list
re:
ICRR