Threaded versus threadless headset



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On Fri, 22 Aug 2003 13:18:00 GMT, Al Frost <[email protected]> wrote:

> [email protected] wrote in news:Rv81b.13860$dk4.490375 @typhoon.sonic.net:
>
>> That depends on whether the old system is a burden on maintenance and safety. I'm going to change
>> because I have had enough problems with quill stems to warrant it. Besides, the safety margin in
>> a 0.975 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.
>>
>> Jobst Brandt [email protected] Palo Alto CA
>>
> Now there's logic for you! Assuming that your 1.25" steerer and your .975" quill were not hollow
> and there were made of similar materials then your conclusion of a higher safety margin would be
> sound. But they are not. The wall thickness of a steerer is much less than that of a quill. Even
> though the outside diameter of the steerer is much larger the quill retains it's strength with
> increased wall thickness. Besides if you are breaking your quills then you need to take up a
> different activity.
>
> AL
>

Personally, I cannot tell any strength difference between my quill stem on my old Trek and the
threadless system on my new LeMond.

--
Bob M in CT Remove 'x.' to reply
 
Al Frost <[email protected]> wrote in news:[email protected]:

> No, most corrosion problems stem from a lack of maintenance! Removing, lubricating and
> reinstalling the quill stem (and seatpin, for that matter) at regular intervals will prevent them
> from sticking.

Yes, and doing that maintenance is a royal pain and has to be done often. Also, I can't get the stem
fully out without undoing cables.

However, there should be a simple way of keeping sweat and water from going down inside the
steerer tube (the O-ring doesn't work). Maybe a rubber boot or a wrap of electrical tape around
the junction.

In my opinion, threadless is better.
 
In article <[email protected]>, [email protected] says...
>
> David L. Johnson wrote in message ...
> >>
> >With a quill stem (that is, with a threaded fork and headset),
>
> Dave, when was the last time you saw anyone riding with those old things, these days everyone ride
> threadless.

I don't know about Dave, but when I looked down momentarily while riding ride yesterday, I saw a
quill stem! Egads!
>
> And if you do see guys with quill stems on the next ride then find another group to ride with,
> because they are the 'B' group. Those are probably the same lamers that are running conventional
> 32 spoke wheels. Not the types you want to been seen with!
>
Yes, you're obviously right. Equipment makes the man.

Rick
 
Al Frost writes:

>> That depends on whether the old system is a burden on maintenance and safety. I'm going to change
>> because I have had enough problems with quill stems to warrant it. Besides, the safety margin in
>> a .975 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.

> Now there's logic for you! Assuming that your 1.25" steerer and your 0.975" quill were not hollow
> and there were made of similar materials then your conclusion of a higher safety margin would be
> sound. But they are not. The wall thickness of a steerer is much less than that of a quill. Even
> though the outside diameter of the steerer is much larger the quill retains it's strength with
> increased wall thickness. Besides if you are breaking your quills then you need to take up a
> different activity.

Oops! The strength of a round cross section is given primarily by its outside diameter. That is why
bicycle frames are made of thin walled tubing instead of solid bars. Most of the aluminum inside the
stem is just excess weight. Meanwhile consider the thin skin of an aircraft.

Jobst Brandt [email protected] Palo Alto CA
 
<[email protected]> wrote in message news:[email protected]...

> Oops! The strength of a round cross section is given primarily by its outside diameter. That is
> why bicycle frames are made of thin walled tubing instead of solid bars. Most of the aluminum
> inside the stem is just excess weight. Meanwhile consider the thin skin of an aircraft.

Hey Jobst, aren't the aluminum walls of a quill stem thicker so they can deal with the compression
load applied when the center bolt is used to tighten the wedge?

-Buck
 
On Fri, 22 Aug 2003 18:17:25 GMT, <[email protected]> wrote:

> Al Frost writes:
>
>>> That depends on whether the old system is a burden on maintenance and safety. I'm going to
>>> change because I have had enough problems with quill stems to warrant it. Besides, the safety
>>> margin in a .975 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.
>
>> Now there's logic for you! Assuming that your 1.25" steerer and your 0.975" quill were not hollow
>> and there were made of similar materials then your conclusion of a higher safety margin would be
>> sound. But they are not. The wall thickness of a steerer is much less than that of a quill. Even
>> though the outside diameter of the steerer is much larger the quill retains it's strength with
>> increased wall thickness. Besides if you are breaking your quills then you need to take up a
>> different activity.
>
> Oops! The strength of a round cross section is given primarily by its outside diameter. That is
> why bicycle frames are made of thin walled tubing instead of solid bars. Most of the aluminum
> inside the stem is just excess weight. Meanwhile consider the thin skin of an aircraft.
>
> Jobst Brandt [email protected] Palo Alto CA

That may be true, but I've ridden the same quill stem for 15 years, and it survived an accident
where I hit a car that turned in front of me. My crank and forks were ruined. I don't know what
units "strength" is in, but let's say that my quill stem has a strength of 500 and the stem on my
threadless system has a strength of 1000. If I've never hurt my quill stem and can't feel any
movement when pulling up on the handlebars, what good is an extra 500 units of strength? Personally,
since I'm having troubles getting my LeMond dialed in, I'd rather to be able to lower and raise the
handlebars (perhaps even during a ride) without taking 15 minutes to take the stem off and switch
spacers. Especially since -- regardless of which system is "stronger" -- I perceive no difference
between the two systems in terms of feel.

--
Bob M in CT Remove 'x.' to reply
 
<[email protected]> wrote:
>David Damerell writes:
>>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 had a stuck quill stem.
>Your testimonial is commonly offered proof on wreck.bike that demonstrates that there are
>exceptions.

Hang on; I am merely challenging here the specific assertion that it is down to rain alone without
the addition of sweat.
--
David Damerell <[email protected]> Distortion Field!
 
David Damerell writes:

> 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 had a stuck quill stem.

Your testimonial is commonly offered proof on wreck.bike that demonstrates that there are
exceptions. If you ask frame repair or bicycle repair shop folks, you'll get a different assessment.
The permanently stuck stem is a recurring subject in this forum to which all sorts of clever
solutions are offered, mostly by people like yourself, who have not had an aluminum stem stuck in a
steel steer tube.

Aluminum oxidizes easily in the steel tube and in so doing causes an oxide that has twice the volume
of the metal from which it is made. This occurs with such force that it expands steer tubes. For
this reason, of all the methods offered, only one, works. The upper (elbow) part of the stem must be
sawed off, drilled out and slit with a Dremel tool to be extracted.

Aside from stuck stems, creaking stems are a common complaint. The quill stem is secured only at its
bottom end and is free to yaw in the upper end of its engagement in the steer tube. This motion
causes water pumping, regardless of whether there is an o-ring in the lock nut or not. For those who
climb hills, sweat drips on that area and the next rain washes it in. For those who don't sweat,
ride hills.

I think if you will review this, you will see that your experience is not that of
bicyclists at large.

Jobst Brandt [email protected] Palo Alto CA
 
Al Frost writes:

> No, most corrosion problems stem from a lack of maintenance! Removing, lubricating and
> reinstalling the quill stem (and seatpin, for that matter) at regular intervals will prevent them
> from sticking.

Another proof that "threadless headsets" are a boon to cyclists who ride much. What do you propose
as a service interval. Should we program our speedometers to warn of needed disassembly?

Jobst Brandt [email protected] Palo Alto CA
 
David Damerell writes:

>> The two main arguments I've heard for threadless seem only to apply to very heavy riders with
>> powerful upper bodies (where "stiffer" is not just a meaningless marketing fact) and people who
>> somehow manage to sweat a lot onto the headset, sticking the quill in place.

> I'm not sure I want to know what's going on atop a bike that's accumulating sweat on the stem.
> *Really* I don't.

I take it you don't ride enough to work up a sweat. Where do you ride? I have friends who were saved
by the advent of good titanium frames to solve their perspiration damage to the bicycle. Maybe you
ought to ride bike in the hills to discover how that happens.

I can think of one that would do the trick:

http://www.paloaltobicycles.com/alps_photos/i11.html

Jobst Brandt [email protected] Palo Alto CA
 
<[email protected]> wrote:
>Werehatrack <[email protected]> writes:
>>David Damerell writes:

I have restored the correct attribution lines here. Please take care not to mangle them. I did
not write the paragraph beginning "I'm not sure", but from your article people would conclude
that I did.

>>>The two main arguments I've heard for threadless seem only to apply to very heavy riders with
>>>powerful upper bodies (where "stiffer" is not just a meaningless marketing fact) and people who
>>>somehow manage to sweat a lot onto the headset, sticking the quill in place.
>>I'm not sure I want to know what's going on atop a bike that's accumulating sweat on the stem.
>>*Really* I don't.
>I take it you don't ride enough to work up a sweat. Where do you ride?

I ride in Britain, which is not exactly flat in places.

>I can think of one that would do the trick: http://www.paloaltobicycles.com/alps_photos/i11.html

While I don't sweat much, I'm sure I'd sweat enough coming up that that droplets would fail to
evaporate and instead trickle off my chin - but if I judge the gradient correctly, my chin would at
that point be a few inches to the rear of my stem!

As I've said before, when I do sweat copiously, it hits me in the knees. I'm not saying it's
not a problem for _some_ riders, but equally there are some people for whom a quill stem is
unlikely to stick.
--
David Damerell <[email protected]> Distortion Field!
 
David Damerell writes:

>>> 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 had a stuck quill stem.

>> Your testimonial is commonly offered proof on wreck.bike that demonstrates that there are
>> exceptions.

> 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. If
that is the case then you may be right. I don't know any riders who have had stuck stems that didn't
ride hills. I suppose a downtown commuter might fit that description but then they usually use steel
stems around here.

Jobst Brandt [email protected] Palo Alto CA
 
On Thu, 21 Aug 2003 18:50:25 GMT, [email protected] wrote:

>That depends on whether the old system is a burden on maintenance and safety. I'm going to change
>because I have had enough problems with quill stems to warrant it. Besides, the safety margin in a
>0.975 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.

Indeed, 0.975 diameter aluminum is not a lot, especially when it is getting gouged by the top edge
of the steer tube. But wouldn't a steel stem solve this problem and the problem of the stuck
stems? Or are those clamps for track bikes that fit on the stem where it goes into the steerer a
better solution?

Jennifer D
 
Buck who? writes:

>> Oops! The strength of a round cross section is given primarily by its outside diameter. That is
>> why bicycle frames are made of thin walled tubing instead of solid bars. Most of the aluminum
>> inside the stem is just excess weight. Meanwhile consider the thin skin of an aircraft.

> Hey Jobst, aren't the aluminum walls of a quill stem thicker so they can deal with the compression
> load applied when the center bolt is used to tighten the wedge?

They were mostly made with a conical expander, for which a thicker body was necessary but when they
switched to the slant wedge, nothing was changed. They easily could have been made thinner. Local
riders bored out the horizontal shaft of Cinelli stems.

Jobst Brandt [email protected] Palo Alto CA
 
David Damerell <[email protected]> wrote in message
news:<DPk*[email protected]>...

<snip>
> The two main arguments I've heard for threadless seem only to apply to very heavy riders with
> powerful upper bodies (where "stiffer" is not just a meaningless marketing fact) and people who
> somehow manage to sweat a lot onto the headset, sticking the quill in place [1].
<snip>
> If, like me, you don't have either of those two problems you are entirely
> [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 don't think I'm unusual
in that respect. That's probably why they make those sweat catchers for trainers long enough to
cover the headset.

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? That's when I notice sweat
getting into my eyes and onto my headset.
 
Jennifer Donleavy writes:

>> That depends on whether the old system is a burden on maintenance and safety. I'm going to change
>> because I have had enough problems with quill stems to warrant it. Besides, the safety margin in
>> a .875 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.

> Indeed, 0.875 diameter aluminum is not a lot, especially when it is getting gouged by the top edge
> of the steer tube. But wouldn't a steel stem solve this problem and the problem of the stuck
> stems? Or are those clamps for track bikes that fit on the stem where it goes into the steerer a
> better solution?

Now that you mention it, that's the setup (with track clamp) I have but I still don't like the way
it performs. I climb hills standing and find the forward reach of the stem and its 0.875 dia post an
unnecessary torsion bar between me and the bicycle. I'm looking forward to a new fork with suitable
steertube to get rid of that.

Jobst Brandt [email protected] Palo Alto CA
 
[email protected] wrote in message news:<[email protected]>...
> Al Frost writes:
>
> >> That depends on whether the old system is a burden on maintenance and safety. I'm going to
> >> change because I have had enough problems with quill stems to warrant it. Besides, the safety
> >> margin in a .975 dia aluminum stem is nowhere near that of a 1.25 dia tubular stem.
>
> > Now there's logic for you! Assuming that your 1.25" steerer and your 0.975" quill were not
> > hollow and there were made of similar materials then your conclusion of a higher safety margin
> > would be sound. But they are not. The wall thickness of a steerer is much less than that of a
> > quill. Even though the outside diameter of the steerer is much larger the quill retains it's
> > strength with increased wall thickness. Besides if you are breaking your quills then you need to
> > take up a different activity.
>
> Oops! The strength of a round cross section is given primarily by its outside diameter. That is
> why bicycle frames are made of thin walled tubing instead of solid bars. Most of the aluminum
> inside the stem is just excess weight. Meanwhile consider the thin skin of an aircraft.

Maybe we should make stems, and bicycles for that matter, from rolled aluminum foil, then.

JP
 
On 22 Aug 2003 13:49:03 -0700, [email protected] (Gary Young) may have 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? That's when I notice sweat
>getting into my eyes and onto my headset.

Good point, although I tend not to drop all the way forward until I'm rolling a little more, as my
shifters aren't conveniently reachable once I'm in the drops.

--
My email address is antispammed; pull WEEDS if replying via e-mail. Yes, I have a killfile. If I
don't respond to something, it's also possible that I'm busy.
 
On Fri, 22 Aug 2003 18:23:27 GMT, [email protected] may have said:

>I take it you don't ride enough to work up a sweat.

In Houston? Getting on the bike could be enough work up a sweat. (In Miami, just going outside to
get on the bike would be enough.)

> Where do you ride? I have friends who were saved by the advent of good titanium frames to solve
> their perspiration damage to the bicycle. Maybe you ought to ride bike in the hills to discover
> how that happens.

I like my flatlands in certain respects. I like hills, too, but I prefer to attack them on foot.

>I can think of one that would do the trick:
>
>http://www.paloaltobicycles.com/alps_photos/i11.html

Some people will just go out of the way to find a challenge. Hey, if they like it, I'll bring
popcorn and watch.

--
My email address is antispammed; pull WEEDS if replying via e-mail. Yes, I have a killfile. If I
don't respond to something, it's also possible that I'm busy.
 
On Fri, 22 Aug 2003 21:07:39 GMT, [email protected] wrote:

>
>Now that you mention it, that's the setup (with track clamp) I have but I still don't like the way
>it performs. I climb hills standing and find the forward reach of the stem and its 0.875 dia post
>an unnecessary torsion bar between me and the bicycle.

Yeah, I know! Are those track clamps even available anymore? I can't find one anywhere. Did you buy
it recently or is it from the old days?

> I'm looking forward to a new fork with suitable steertube to get rid of that.

What about a steel stem? That's the solution I am considering -- having a tubular steel stem tig
welded by a local frame builder. Would that be a good, safe solution? Do they break from the
notching like I am expecting my current stem to do?

Jennifer D
 
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