Threaded versus threadless headset

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

Quoted message said:

In article <[email hidden]>, [email hidden]

(JP) said:

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

Quoted message said:

We would, except for the "beer-can effect" of too-easy denting. Really light aluminum road
frames and some MTB monocoque frames (the Norco VPS bikes come to mind) already push the
limits of frame wall thinness against the limits of reasonable dent resistance.

So you're saying that ultra thin wall aluminum frames aren't strong enough? At this extreme
strength is not simply derived from the diameter of the tubing, it's based on frame design, the
way the tubes are arranged, just as an airplane's aluminum skin would be inadequate without its
internal skeleton. Try folding an empty beer can. Its weakness is not just observable as
proneness to denting.

No, I'm saying that thin-wall aluminum frames are quite strong in the ways that matter for a
cyclist: they're stiff and resist being compressed, flexed, or twisted.

According to you dent resistance seems to matter, and according to you, it is an issue with thin
wall aluminum frames.

Quoted message said:

The arrangement of tubes on a UCI-legal bicycle is largely fixed: there is little leeway for one
design to have a more rigid arrangement of tubes than another, for the same material in the same
dimensions.

So? That is completely irrelevant. My point is that the design, which you say is mandated by the
UCI, provides the strength for a bicycle frame. Imagine one of your thin wall aluminum frames
without a top tube or down tube. It has almost not strength at all. It would collapse like an
empty beer can.

Quoted message said:

Dent resistance isn't part of what happens to a bike when it gets ridden, but bikes need some
dent-resistance so they don't get dented when not being ridden, especially since dents in round
tubes (or in the wrong place on any tube) greatly compromise strength.

Dent resistance is a function of tube strength. A tube that will dent easily will fold easily if it
is not braced.

Quoted message said:

Empty beer cans do fold easily, but they don't need dent resistance at that point in their life,
and their walls are less than .013" thick.

Exactly.

Quoted message said:

Internal gusseting can make any design stronger, but for a given weight, it's not the way to go,
since you can get more strength (at least against torsional and bending loads) by making the
cylinder diameter larger.

Full beer cans have effective internal gusseting. It is a result of the can's pressurized contents.
I have had the misfortune on a couple of occasions to get a can of flat beer. I knew something was
wrong when I crushed it in the process of getting it out of the refrigerator. Try this simple
experiment (requires wasting a perfectly good can of beer): drill a tiny hole in a beer can and then
let the beer sit for a couple of weeks to go flat. Test how easy it is to dent or fold.

Bike frames have external gusseting- the frame structue itself.

Quoted message said:

An aircraft's skin is a stressed structure, a "monocoque" design. The frame inside the skin is
part of the structural strength of a plane, but not as much as you would think.

You might be surprised what I would think.

Quoted message said:

One important function the inner frame provides is a place to mount interior fittings. Meanwhile
the important job of keeping the aircraft from twisting, flexing, or folding is done mostly by the
exterior skin, not the inner frame.

That's absurd. It's a combination of both the frame and the skin.

Quoted message said:

Quoted message said:

Strength is a function of both tube diameter and tube wall thickness, not to mention alloy and
heat treatment properties.

It is, but the former completely dwarfs the latter, and the last two aren't part of this
discussion.

Yes they are.

(snipped)

Quoted message said:

Going back to the beer can analogy, it's easy to dent an empty beer can, and a dented beer can is
much easier to crush than an undented one, because it collapses around the dent, causing more
folding and "dents", and then the thing loses all resemblance to a tube and falls down.

And an thin-walled aluminum bicycle frame without a top tube or a down tube will do the same thing.

Quoted message said:

It's a positive attribute of a design which has other more important advantages: threadless stems
have no quill to seize or invisibly bulge the steer tube. As several have already noted, these
advantages are not enough that most of us need to rush out and change our headsets, but all things
being equal, threadless is preferable.

Speak for yourself. While I think the threadless-type stems look cool, I think that adjustibility
trumps looks and a small weight advantage. Even someone getting a custom built bike might at some
time want to change the handlebar height without having to go out and buy a new stem.

Quoted message said:

As for the adjustability issue, stem reach is at least as important as stem height for
establishing a proper fit, but nobody seems to mention that if anything, it is much easier to
change out a threadless stem for one of different reach than it is to change many threaded
stems, since a threaded stem without much excess cable may require detaching cables to fully
remove the stem.

Now this is a good point. However, a properly fitted bike should have the right reach stem on it,
or have to be changed only once, unless your arms grow. We have seen from the comments here that
lowering the bars as conditioning improves is a common practice. It used to be a standard
practice for someone taking up cycling as a serious sport. It's no longer an easy recommendation
to make to a novice.

It is possible to buy quill stems that allow removal of the handlebars (I have one), so the issue
there is only whether there would be enough slack in the cables to use a longer extension (there
probably isn't) - the same issue you would have with a threadless stem.

Quoted message said:

Not to mention that while removable-cap threadless stems are nearly universal, removable-cap
threaded stems are at best only moderately available.

Not really. If you want one, all you have to do is buy it. And there is no doubt about it- they are
better quill stem designs than the ones without the removable cap. So this design feature is
obviously separate from the threadless/quill question.

Quoted message said:

If you're trying to get your handlebars into the right position by adjusting the height without
changing the reach, you're just trying to get an ill-fitting bike into the least-worst position!

Not at all! The stem reach is as fundamental to sizing a bike as seat tube height, maybe more so
since the saddle height is adjustable. Get the reach right and then tweak the height as your fitness
and needs require. Many people clearly have a requirement to change the height within the parameters
of a stem wit a proper reach.

JP

In rec.bicycles.misc Ryan Cousineau <[email hidden]> wrote:
: Fair enough, but in bicycles, simple dent-resistance will be more important than compressive
: buckling. That is, the tube thinness in bicycles is dictated by the inability of the tube to
: withstand normal handling in non-riding modes (or stupid stuff like your knee hitting the top tube
: while riding).

geez, ryan. i thought you were an english major or something. fabrizio never talks like this. making
sense, i mean. what gives?
--
david reuteler [email hidden]

In article <[email hidden]>, [email hidden]

(JP) said:

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

Quoted message said:

In article <[email hidden]>, [email hidden]

(JP) said:

Ryan Cousineau <[email hidden]> wrote in message
news:<[email hidden]>...
> We would, except for the "beer-can effect" of too-easy denting. Really light aluminum road
> frames and some MTB monocoque frames (the Norco VPS bikes come to mind) already push the
> limits of frame wall thinness against the limits of reasonable dent resistance.

So you're saying that ultra thin wall aluminum frames aren't strong enough? At this extreme
strength is not simply derived from the diameter of the tubing, it's based on frame design,
the way the tubes are arranged, just as an airplane's aluminum skin would be inadequate
without its internal skeleton. Try folding an empty beer can. Its weakness is not just
observable as proneness to denting.

No, I'm saying that thin-wall aluminum frames are quite strong in the ways that matter for a
cyclist: they're stiff and resist being compressed, flexed, or twisted.

According to you dent resistance seems to matter, and according to you, it is an issue with thin
wall aluminum frames.

Well, yes. It's the limit at which frames stop getting any thinner. But frame walls are already very
thin. For all practical purposes, the trend in building frames is to make the tubes bigger and the
walls thinner, until the walls would be so thin that while the frame could withstand the loads
imposed by riding the bike, it wouldn't withstand frame tube side-impacts, a likely occurence only
when the bike isn't being normally ridden. I used the Norco VPS as an example of this: a bike which
has a reputation for extreme strength in service, but has frame walls so thin that they can be
dented fairly easily.

To put it another way, once you get the bike's frame tubes so thin that you can't go any thinner
because they will dent too easily, then suppose you wanted to add material to the tubes to make the
frame stronger. The greatest strength gain for a set amount of added frame material would come from
keeping the wall thickness constant but making the tube bigger. if you just made the walls thicker,
the thick-wall tube would not be as strong as the larger-diameter tube.

This is the abstract view, and things get slightly complicated on real bikes because of issues like
butted tubing and non-round tubes. But the essential point that wall thickness is vastly less
important than tube diameter (and that the primary limits on wall thickness in practice have more to
do with load considerations that don't happen while the bike is being ridden) remains.

Quoted message said:

Quoted message said:

The arrangement of tubes on a UCI-legal bicycle is largely fixed: there is little leeway for one
design to have a more rigid arrangement of tubes than another, for the same material in the same
dimensions.

So? That is completely irrelevant. My point is that the design, which you say is mandated by the
UCI, provides the strength for a bicycle frame. Imagine one of your thin wall aluminum frames
without a top tube or down tube. It has almost not strength at all. It would collapse like an
empty beer can.

Sure, but that has nothing to do with frame wall thickness, or even material. If you removed the top
tube or down tube from my lugged steel Pinarello, it would also collapse like an empty beer can. If
it lasted any longer, it would be overdesigned. Granted, a steel frame might do some pretty
impressive bending into new shapes before it failed. But then, a fancy aero aluminum frame with no
top tube might survive just as long, or longer, depending on the shape of the down tube and how good
the head tube weld was. It is left as an exercise for the reader why this might be so.

Quoted message said:

Quoted message said:

Dent resistance isn't part of what happens to a bike when it gets ridden, but bikes need some
dent-resistance so they don't get dented when not being ridden, especially since dents in round
tubes (or in the wrong place on any tube) greatly compromise strength.

Dent resistance is a function of tube strength. A tube that will dent easily will fold easily if
it is not braced.

No, that is categorically wrong. A tube that will dent easily may well be extraordinarily hard to
fold, as long as nobody has already dented
it. You can test this for yourself: take a cardboard paper towel roll core, and do a little
load test on it whereby you hang weight on the top of it until it folds. Now do the test a
second time on this pre-dented tube, or if you fear it may compromise the experiment, on a
second, identical, but pre-dented cardboard tube. The second tube will hold much less load
before folding.

Better yet, test this with the tube in compression, since that's typical of the loads on a top tube.

These experiments will demonstrate that dents precede and precipitate tube collapse.

You seem to be arguing that a tube that can be easily dented will fold if not braced. That is only
true at the very extreme of tube wall thickness, a realm which bike tubes don't enter, but only
because they start to get dented. If they didn't get dented by ordinary wear and tear, they could be
even thinner.

Quoted message said:

Quoted message said:

Empty beer cans do fold easily, but they don't need dent resistance at that point in their life,
and their walls are less than .013" thick.

Exactly.

But even so, they're extraordinarily strong for their weight!

Quoted message said:

Quoted message said:

Internal gusseting can make any design stronger, but for a given weight, it's not the way to go,
since you can get more strength (at least against torsional and bending loads) by making the
cylinder diameter larger.

Full beer cans have effective internal gusseting. It is a result of the can's pressurized
contents.

Yes, but full beer cans are really heavy! They contain over a half-pound of beer. I could make your
bike (almost any bike) stronger by filling the tubes with liquid, but the bike would be stupidly
heavy. The beer has to be there, and you can't reduce its weight or volume, so the strength it adds
to the structure is essentially free of engineering trade-offs. There is no comparable amount of
"free" weight or structure in the design of a bike frame.

Quoted message said:

Bike frames have external gusseting- the frame structue itself.

That's not external gusseting of the tubes. Indeed, I don't even know what you are talking about. A
conventional non-lugged bike frame is one of the least-gusseted structures in common use. It's
nothing but tubes butt-welded to each other.

Quoted message said:

Quoted message said:

An aircraft's skin is a stressed structure, a "monocoque" design. One important function the
inner frame provides is a place to mount interior fittings. Meanwhile the important job of
keeping the aircraft from twisting, flexing, or folding is done mostly by the exterior skin, not
the inner frame.

That's absurd. It's a combination of both the frame and the skin.

Sure, but the frame is like the beer in a beer can. Since it has to be there to keep the innards of
the airplane in place anyways, clever engineering can take advantage of that structure to make the
outer airframe even lighter.

Quoted message said:

Quoted message said:

Quoted message said:

Strength is a function of both tube diameter and tube wall thickness, not to mention alloy and
heat treatment properties.

It is, but the former completely dwarfs the latter, and the last two aren't part of this
discussion.

Yes they are.

No they aren't. All conventional materials are going to have the same strength relationship between
tube diameter and wall thickness. If I made a bicycle out of hollow wood (or preferably, plastic,
since it would remove the dicey issues of grain and materials consistency), I would still build a
stronger frame for a given weight of material by making the tubes thinner and bigger right up to the
point where they didn't withstand ordinary wear and tear.

Quoted message said:

Quoted message said:

It's a positive attribute of a design which has other more important advantages: threadless
stems have no quill to seize or invisibly bulge the steer tube. As several have already noted,
these advantages are not enough that most of us need to rush out and change our headsets, but
all things being equal, threadless is preferable.

Speak for yourself. While I think the threadless-type stems look cool, I think that adjustibility
trumps looks and a small weight advantage. Even someone getting a custom built bike might at some
time want to change the handlebar height without having to go out and buy a new stem.

Then choose your steer-tube cut judiciously. It's nothing to put a couple of cm of spacers under
your stem and then choose a stem accordingly. As long as you make that choice up front, you can have
lots of bar-height adjustment without changing your stem. Not to mention that any non-zero-rise stem
automatically offers two bar heights: normal, and flipped over.

Quoted message said:

Quoted message said:

As for the adjustability issue, stem reach is at least as important as stem height for
establishing a proper fit, but nobody seems to mention that if anything, it is much easier to
change out a threadless stem for one of different reach than it is to change many threaded
stems, since a threaded stem without much excess cable may require detaching cables to fully
remove the stem.

Now this is a good point. However, a properly fitted bike should have the right reach stem on it,
or have to be changed only once, unless your arms grow. We have seen from the comments here that
lowering the bars as conditioning improves is a common practice. It used to be a standard practice
for someone taking up cycling as a serious sport. It's no longer an easy recommendation to make to
a novice.

The reason people lower bars is because it is easy. A lot of time these riders may not be optimizing
their position either from an aerodynamic or power-generating point of view, because they don't
bother changing the stem reach. I raised this point about the non-adjustability of a quill stem half
in jest, but mainly to make the point that a single quill stem will not provide a complete set of
fit options for one rider, and only a little more (at most) than one threadless stem will.

Quoted message said:

Quoted message said:

If you're trying to get your handlebars into the right position by adjusting the height without
changing the reach, you're just trying to get an ill-fitting bike into the least-worst position!

Not at all! The stem reach is as fundamental to sizing a bike as seat tube height, maybe more so
since the saddle height is adjustable. Get the reach right and then tweak the height as your
fitness and needs require. Many people clearly have a requirement to change the height within the
parameters of a stem wit a proper reach.

The only reason we fit stem reach (as opposed to height) as the "fundamental" is because it is hard
to change the reach after: you have to buy a new stem. Height allows fine-tuning of the pre-set
reach if you like, but the real goal is to get both adjustments correct in one shot.

I daresay that a serious rider would benefit from changes of stem reach at the same time as the stem
height was changed in some cases, but we'll never know, because the tyranny of the
nonadjustable-reach quill stem keeps us ignorant! 🙂

Seriously, that's a trivial detail issue.

--
Ryan Cousineau, [email hidden] sfu.ca~rcousineOpen ↗ President, Fabrizio Mazzoleni Fan Club

Quoted message said:

Quoted message said:

Full beer cans have effective internal gusseting. It is a result of the can's pressurized
contents.

Yes, but full beer cans are really heavy! They contain over a half-pound of beer. I could make
your bike (almost any bike) stronger by filling the tubes with liquid, but the bike would be
stupidly heavy. The beer has to be there, and you can't reduce its weight or volume, so the
strength it adds to the structure is essentially free of engineering trade-offs. There is no
comparable amount of "free" weight or structure in the design of a bike frame.

Has anyone ever tried a pressurised frametubes......but with Nitrogen, not beer! Following this
thread it seems that if tube denting was the limiting factor it would make a difference. Sort of
like prestressed concrete in reverse as its buckling not tension we're worried about.

Though come to think of it I'm surprised I've never seen a bike where the seattube was the
waterbottle - probably a better idea than beer I guess

Hugh Fenton

On Mon, 25 Aug 2003 18:46:16 -0700, Ryan Cousineau <[email hidden]> from WAC Bennett Review of Arts

and Literature said:

Must...advocate...low-spoke-count...wheels...make it up to Jobst...later!

Spokes? You only need three -- Hed 3's are suitable for all serious cycling.

--
home.sport.rr.comcuthuluOpen ↗ human rights = peace I'm rated PG-34!!
9:38:14 PM 25 August 2003

On Tue, 26 Aug 2003 04:16:54 GMT, "Fabrizio Mazzoleni" <[email hidden]> from Shaw Residential

Internet said:

Have you checked out the white PBO fiber spokes on the Spinergy Tilium Carbons? They are running 16
on the front which is better than having 18 of those lame oval spokes on the Zipp 404s.

The Rolf Prima Carbon is running 14 up front and 16 in the rear. It's still "in development," but if
you know the right aero people, you can get some.

--
home.sport.rr.comcuthuluOpen ↗ human rights = peace UH-OH!! I put on "GREAT HEAD-ON TRAIN
COLLISIONS of the 50's" by mistake!!!
12:25:15 AM 26 August 2003

In article said:

In rec.bicycles.misc Ryan Cousineau <[email hidden]> wrote:
: Fair enough, but in bicycles, simple dent-resistance will be more important than compressive
: buckling. That is, the tube thinness in bicycles is dictated by the inability of the tube to
: withstand normal handling in non-riding modes (or stupid stuff like your knee hitting the top
: tube while riding).

geez, ryan. i thought you were an english major or something. fabrizio never talks like this.
making sense, i mean. what gives?

Well, I'm trying to be more like Fabrizio, but it's hard. I was raised by an engineer, and spent a
lot of time in the applied sciences at university before it became clear that I'd better start
playing to my strengths, which is to say rhetoric, which is why I did a BA.

Must...advocate...low-spoke-count...wheels...make it up to Jobst...later!
--
Ryan Cousineau, [email hidden] sfu.ca~rcousineOpen ↗ President, Fabrizio Mazzoleni Fan Club

Kevan Smith wrote in message ...

Quoted message said:

Spokes? You only need three -- Hed 3's are suitable for all serious cycling.

I find tri-spokes to be too clunky looking.

Some of my peers were looking ok at this year's TdF running deep section carbs with straight-pull
flat section spokes, like on the Cosmic Carbone SSC.

Have you checked out the white PBO fiber spokes on the Spinergy Tilium Carbons? They are running 16
on the front which is better than having 18 of those lame oval spokes on the Zipp 404s.

Remember you are what you ride, don't be a FRED.

In article said:

Quoted message said:

Quoted message said:

Full beer cans have effective internal gusseting. It is a result of the can's pressurized
contents.

Yes, but full beer cans are really heavy! They contain over a half-pound of beer. I could make
your bike (almost any bike) stronger by filling the tubes with liquid, but the bike would be
stupidly heavy. The beer has to be there, and you can't reduce its weight or volume, so the
strength it adds to the structure is essentially free of engineering trade-offs. There is no
comparable amount of "free" weight or structure in the design of a bike frame.

Has anyone ever tried a pressurised frametubes......but with Nitrogen, not beer! Following this
thread it seems that if tube denting was the limiting factor it would make a difference. Sort of
like prestressed concrete in reverse as its buckling not tension we're worried about.

Close. Bianchi famously does foam-filled frame tubes, a very clever idea. The problem is that even
foam has some weight:

gianni.bianchiusa.comrepartoOpen ↗

Quoted message said:

Though come to think of it I'm surprised I've never seen a bike where the seattube was the
waterbottle - probably a better idea than beer I guess

Getting the seat tube close enough to your mouth to take a drink would be tricky. How about an
internally routed Camelbak in the top tube? Heck, on a Norco VPS you could just fit an entire
regular Camelbak bladder into the monocoque.

--
Ryan Cousineau, [email hidden] sfu.ca~rcousineOpen ↗ President, Fabrizio Mazzoleni Fan Club

Hugh Fenton said:

Quoted message said:

Quoted message said:

Full beer cans have effective internal gusseting. It is a result of the can's pressurized
contents.

Quoted message said:

Quoted message said:

Yes, but full beer cans are really heavy! They contain over a half-pound of beer. I could make
your bike (almost any bike) stronger by filling the tubes with liquid, but the bike would be
stupidly heavy. The beer has to be there, and you can't reduce its weight or volume, so the
strength it adds to the structure is essentially free of engineering trade-offs. There is no
comparable amount of "free" weight or structure in the design of a bike frame.

Quoted message said:

Has anyone ever tried a pressurised frametubes......but with Nitrogen, not beer! Following this
thread it seems that if tube denting was the limiting factor it would make a difference. Sort of
like prestressed concrete in reverse as its buckling not tension we're worried about.

Well it ain't so. Those who re-cycle beverage cans know that thin walled tubes (beer and soda
cans) collapse axially easily with a slight vertical thrust while standing on them. Bending a
tube, such loads are easily achieved. Sitting on the top tube of a bicycle exerts such forces. The
pressure in the tube (can), unless extremely high, has little effect on such wrinkling. You can do
this to a full beer can easily by stomping on it. It just won't do more than get a few wrinkles
before liquid incompressibility arrests further collapse. To prevent collapse, you could fill your
frame with water.

What an idea!

Jobst Brandt [email hidden] Palo Alto CA

In article <[email hidden]>, [email hidden] says...

Quoted message said:

Hugh Fenton said:

Quoted message said:

> Full beer cans have effective internal gusseting. It is a result of the can's pressurized
> contents.

Quoted message said:

Quoted message said:

Yes, but full beer cans are really heavy! They contain over a half-pound of beer. I could make
your bike (almost any bike) stronger by filling the tubes with liquid, but the bike would be
stupidly heavy. The beer has to be there, and you can't reduce its weight or volume, so the
strength it adds to the structure is essentially free of engineering trade-offs. There is no
comparable amount of "free" weight or structure in the design of a bike frame.

Quoted message said:

Has anyone ever tried a pressurised frametubes......but with Nitrogen, not beer! Following this
thread it seems that if tube denting was the limiting factor it would make a difference. Sort of
like prestressed concrete in reverse as its buckling not tension we're worried about.

Well it ain't so. Those who re-cycle beverage cans know that thin walled tubes (beer and soda
cans) collapse axially easily with a slight vertical thrust while standing on them. Bending a
tube, such

Well, sort of. Have you ever tried the trick of standing on one foot on an empty soda can, showing
that it can hold your weight (190 lb in my case), and then lightly tap the sides with your fingers,
and it suddenly collapses (on your fingers if you're not quick)? Demonstrates the effect perfectly,
that an undented thin-walled tube can support significant loads, but the collapses at the slightest
damage to the walls. It's a fun demonstration to show your kids.

Of course, if you stomp on the can, you are imparting uneven or lateral loads on it to initiate the
buckling, so it collapses immediately.

....

--

"Where was the ka-boom? There was supposed to be an Earth-shattering ka- boom!"
- Marvin The Martian

Quoted message said:

David Damerell said:

Hang on; I am merely challenging here the specific assertion that it is down to rain alone without
the addition of sweat.

It still boils down to that you don't sweat and probably don't ride long hills... in the summer.

It is still the case that I ride in all weathers - including fine weather
- and Britain is still not flat. As I've said, when I do sweat sufficiently that it cannot
evaporate, it doesn't land anywhere near my stem.

I'm not saying that this cannot be a problem for some riders, but some of us are fortunate and may
continue to use quill stems without fear of them sticking.
--
David Damerell <[email hidden]> Distortion Field!

Peter Cole said:

"David Damerell" <[email hidden]> wrote in message

Quoted message said:

I doubt it. I have ridden in Britain in all weathers for many years, and only in the last couple
of years acquired a cycling cape (which covers the stem - even then, the bike is periodically
parked in the rain). I've never has a stuck quill stem.

All of my bikes show rust inside the steertube. Perhaps it's accelerated by the salt compounds used
to treat the roads here in New England,

Because the roads are never salted here? I think not.

It's not clear to me how a significant quantity of water carrying gunk from the road surface could
end up inside the steer tube, unless the bike lacks a front mudguard.

Quoted message said:

but such corrosion and stuck quills/seatposts seem to not be a strictly salted road phenomenon,
judging from the posts here over the years.

I suspect it has nothing to do with salted roads, but everything to do with the subset of riders who
sweat onto the stem and headset.
--
David Damerell <[email hidden]> Distortion Field!

James Thomson said:

David Damerell said:

I have a threaded fork with a Nitto quill stem - to get the same bar position with a threadless
headset would demand a very unusually shaped stem.

longer-than-average steerer, or a steerer extender. On the other hand, to raise your bars to their
present height required an unusually-shaped stem: a Nitto Technomic.

Well, I'm not disputing that most of the quill stems that came with bikes are just as pointlessly
low as the threadless equivalents that come with bikes now...
--
David Damerell <[email hidden]> Distortion Field!

Gary Young said:

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

Quoted message said:

[1] I still don't see how this happens - the head is usually at least somewhat aft of the bars,
and the apparent wind will blow droplets of sweat to the rear. When I sweat enough that it
cannot evaporate it hits me on the knees, not on the headset!

When I'm riding my road bike, my head is almost directly over the headset.

I looked and I see this is the case for me when riding in the drops - I have my bars mounted quite
high, so I ride in the drops most of the time and in the hoods uphill, which I find most
comfortable.

When climbing a steep hill there is little apparent wind, but then the combination of riding in the
hoods and the slope _has_ moved my head definitely to the rear of the headset.

Quoted message said:

You're right that apparent wind keeps the sweat away most of the time, but what about when you've
made a hard effort on a hot day and then have to stop for a light?

If I'm going to be there for any length of time I let go of the bars and stand upright.
--
David Damerell <[email hidden]> Distortion Field!

"Hugh Fenton" <[email hidden]> a écrit > >

Quoted message said:

Has anyone ever tried a pressurised frametubes......but with Nitrogen, not beer! Following this
thread it seems that if tube denting was the limiting

factor

Quoted message said:

it would make a difference. Sort of like prestressed concrete in reverse

as

Quoted message said:

its buckling not tension we're worried about.

It's a great idea in theory. However, if you want it to work, you need an uncompressible product.
IOW, filling tubes with air doesn't work. It might work if the tubes were compressed with air at
1000 - 2000 psi, but then the tubes would be 2-3 mm thick (ballpark figure, I haven't actually done
the maths), and such thick tubes wouldn't be dented anyway.

Filling tubes with water, oil or another liquid like that would work, but then weight would be
problematic.

Quoted message said:

Though come to think of it I'm surprised I've never seen a bike where the seattube was the
waterbottle - probably a better idea than beer I guess

That would be a good idea in theory. A few problems however:
- sealing the tube, and especially the bottom bracket to prevent contamination;
- sipping the liquid;
- cleaning the tubes once in a while;
- installing a fitting for the hose and for the filling outltet, without inducing stresspoints. An
easy solution: get thicker tubes... As you see, we won't see that soon. BTW, water capacity of the
seat tube of a road bike would be 175-225 mL.

Regards,

Michel

In my opinion, no real differences. Threadless makes adjustment easier, but a well-adjusted
threaded shoud never need adjustment. The real reason for the whole threadless thing goes back to
mountain-bikes. It was a huge inventory pain in the ass to keep forks around with 5-9 steerer
tube diameters/length combinations. Imagine the bike companies needing hundreds of thousands of
forks, some 1 inch, some 1 1/8 inch, some 1 1/4'. Some threaded, some not. So make them all the
same diameter, 1 1/8 seemed about right, make them threadless and then you only need 1 steerer
tube ( long) and it could be trimmed to length as needed. Then, convince the public that this is
lighter, safer, cheaper and better and they'll buy in. By the way, it generally isn't lighter,
costs about the same to us ( though is cheaper for the manufacturers). is easier to set up and
adjust. So it wasn't all bad. But on road bikes? Answers a question nobody asked. But it did make
it easier on shops not having to stock 8 different lengths of each carbon replacement fork. 1
long one was enough.

David Damerell said:

Well, I'm not disputing that most of the quill stems that came with bikes are just as pointlessly
low as the threadless equivalents that come with bikes now...

I didn't think for a moment that you were: you were clearly saying that an unusual A-head stem would
be needed to put your bars where your unusual quill stem now puts them.

The fact that some quill stems and some threadless steerers are too short to allow some riders to
find their favoured position is an argument for providing longer-quilled stems for those who require
them, and supplying threadless forks with long, uncut steerers. It has little to do with the
relative merits of the two systems.

James Thomson

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

Quoted message said:

In my opinion, no real differences. Threadless makes adjustment easier,

but a

Quoted message said:

well-adjusted threaded shoud never need adjustment. The real reason for

the

Quoted message said:

whole threadless thing goes back to mountain-bikes. It was a huge

inventory

Quoted message said:

pain in the ass to keep forks around with 5-9 steerer tube

diameters/length

Quoted message said:

combinations. Imagine the bike companies needing hundreds of thousands of forks, some 1 inch, some
1 1/8 inch, some 1 1/4'. Some threaded, some not.

So

Quoted message said:

make them all the same diameter, 1 1/8 seemed about right, make them

threadless

Quoted message said:

and then you only need 1 steerer tube ( long) and it could be trimmed to

length

Quoted message said:

as needed. Then, convince the public that this is lighter, safer, cheaper

and

Quoted message said:

better and they'll buy in. By the way, it generally isn't lighter, costs

about

Quoted message said:

the same to us ( though is cheaper for the manufacturers). is easier to

set up

Quoted message said:

and adjust. So it wasn't all bad. But on road bikes? Answers a question

nobody

Quoted message said:

asked. But it did make it easier on shops not having to stock 8 different lengths of each carbon
replacement fork. 1 long one was enough.

Used to be that one long steerer steel fork was good to keep around for an emergency. Then all you
had to do is thread down to the right length and cut. Voila! Instant custom length fork steerer.

Mike

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

Quoted message said:

I suspect it has nothing to do with salted roads, but everything to do with the subset of riders
who sweat onto the stem and headset.

It may also have to do with rider size and riding style. Jobst has pointed out that the quill stem
is unsupported at the top of the steertube, allowing flex to mix water and grease, and thwarting
most efforts to effectively seal the junction. I would expect that large, aggressive, cyclists would
see a much more pronounced effect there. We also (obviously) run a greater risk of stem failure.
Perhaps that is why (Jobst &😉 I have seen both, and you have seen neither.