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-   -   A hole in the stem (http://www.cyclebanter.com/showthread.php?t=257326)

Joy Beeson April 13th 19 04:15 AM

A hole in the stem
 


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?

--
joy beeson at comcast dot net
http://wlweather.net/PAGESEW/
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.



jOHN b. April 13th 19 05:20 AM

A hole in the stem
 
On Fri, 12 Apr 2019 23:15:03 -0400, Joy Beeson
wrote:



I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


I suppose that drilling a hole in part of the steering may be
considered as a poor idea but on the other hand if you have been
riding the bike for a long time with no problems I might be inclined
not to worry about it too much.

Of course, handle bar stems are not exactly what one would term
"expensive". Amazon lists a "Big Roc 57SYC80PK Handle Bar Stem, 22.2 x
80 x 145mm, Alloy" for $15.55 (in pink) and a Sunlite Adjustable Quill
Stem, 22.2 x 90 x 180mm, Silver for $19.95, or contact Andrew Muzi for
(perhaps) a better quote.
--
cheers,

John B.


Sir Ridesalot April 13th 19 11:58 AM

A hole in the stem
 
On Friday, April 12, 2019 at 11:15:09 PM UTC-4, Joy Beeson wrote:
I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?

--
joy beeson at comcast dot net
http://wlweather.net/PAGESEW/
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.


If you want to raise or lower a stem with a hole in it to which the front brake cable is anchored then you'd have to adjust the brakes too as lower the stem will move the pads away from the rim and raising the stem will move the pads closer to the rim.

Cheers

Cheers

AMuzi April 13th 19 02:29 PM

A hole in the stem
 
On 4/12/2019 10:15 PM, Joy Beeson wrote:


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


Yes it's a point of stress concentration on a part not
overly strong and, in the classic era of cast aluminum, your
stem may well have voids or inclusions you can't see.

That said, there's plenty of 'prior art':
http://www.yellowjersey.org/photosfromthepast/am19f.jpg

I've seen plenty of failed cast aluminum stems, old and new:
http://pardo.net/bike/pic/fail-001/FAIL-057.html

which is not to say welded stems are immune:
http://pardo.net/bike/pic/fail-001/FAIL-101.html

but haven't seen an actual failure from a hole drilled in a
stem.

So, yes, it's a bad idea in principle but may be OK in
practice. Given its age (aluminum does age-harden) and the
low cost of a forged or thixoform stem, change it if that
bothers you.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971



AMuzi April 13th 19 02:32 PM

A hole in the stem
 
On 4/13/2019 5:58 AM, Sir Ridesalot wrote:
On Friday, April 12, 2019 at 11:15:09 PM UTC-4, Joy Beeson wrote:
I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?

--
joy beeson at comcast dot net
http://wlweather.net/PAGESEW/
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.


If you want to raise or lower a stem with a hole in it to which the front brake cable is anchored then you'd have to adjust the brakes too as lower the stem will move the pads away from the rim and raising the stem will move the pads closer to the rim.



Back when that was the standard setup on MTBs, we saw that
as a feature, not a problem.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971



Sir Ridesalot April 13th 19 05:17 PM

A hole in the stem
 
On Saturday, April 13, 2019 at 9:32:09 AM UTC-4, AMuzi wrote:
On 4/13/2019 5:58 AM, Sir Ridesalot wrote:

Snipped
If you want to raise or lower a stem with a hole in it to which the front brake cable is anchored then you'd have to adjust the brakes too as lower the stem will move the pads away from the rim and raising the stem will move the pads closer to the rim.



Back when that was the standard setup on MTBs, we saw that
as a feature, not a problem.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971


Until you go to raise that stem and it causes the brake pads to bind against the rim. I remember having that happen a lot on those MTBs that had the hole in the stem with the brake cable going through it.

Cheers

Frank Krygowski[_4_] April 13th 19 06:30 PM

A hole in the stem
 
On 4/12/2019 11:15 PM, Joy Beeson wrote:


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


The hole causes what's called "stress concentration." That means when
there's a significant load on the stem, stresses will be higher in the
area right around the hole than they would have been without the hole.

Stress concentration is more of a problem for aluminum than for steel,
for reasons I won't go into here (unless asked). But it's not
necessarily a significant problem. Everyone accepts holes in aluminum
hubs (to attach spokes). I have holes drilled in my aluminum frame to
attach shift levers, bottle cages, etc. The problems arise only if the
concentrated stresses are higher than what the metal can resist for the
long term.

I gather from your posts that you're probably not a person who does lots
of high torque pedaling on sprints or tough climbs, where you're yanking
hard on the handlebars. Those yanks would put torque on the stem and
might generate some significant stress. But I doubt you'll see a problem.

More significant, perhaps, is that the hole is already there. If you
don't use the hole it doesn't improve the situation; it's still a stress
concentration. So leaving the cable out of the hole seems silly to me.

So I'd use it as intended. If you want to be super-diligent, check it
once a month to see if any tiny cracks are emanating from it. If you
want to be paranoid, replace the stem.


--
- Frank Krygowski

Sir Ridesalot April 13th 19 07:00 PM

A hole in the stem
 
On Saturday, April 13, 2019 at 1:30:53 PM UTC-4, Frank Krygowski wrote:
On 4/12/2019 11:15 PM, Joy Beeson wrote:


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


The hole causes what's called "stress concentration." That means when
there's a significant load on the stem, stresses will be higher in the
area right around the hole than they would have been without the hole.

Stress concentration is more of a problem for aluminum than for steel,
for reasons I won't go into here (unless asked). But it's not
necessarily a significant problem. Everyone accepts holes in aluminum
hubs (to attach spokes). I have holes drilled in my aluminum frame to
attach shift levers, bottle cages, etc. The problems arise only if the
concentrated stresses are higher than what the metal can resist for the
long term.

I gather from your posts that you're probably not a person who does lots
of high torque pedaling on sprints or tough climbs, where you're yanking
hard on the handlebars. Those yanks would put torque on the stem and
might generate some significant stress. But I doubt you'll see a problem.

More significant, perhaps, is that the hole is already there. If you
don't use the hole it doesn't improve the situation; it's still a stress
concentration. So leaving the cable out of the hole seems silly to me.

So I'd use it as intended. If you want to be super-diligent, check it
once a month to see if any tiny cracks are emanating from it. If you
want to be paranoid, replace the stem.


--
- Frank Krygowski


Her brake cable is already outside of the hole in the stem. Why should she have the housing shortened and all the work done to put the cable through the stem when braking won't be improved one iota but she'll have problems if in the future she wants to either raise or lower her stem?

Cheers

[email protected] April 13th 19 08:10 PM

A hole in the stem
 
On Saturday, April 13, 2019 at 1:00:23 PM UTC-5, Sir Ridesalot wrote:
On Saturday, April 13, 2019 at 1:30:53 PM UTC-4, Frank Krygowski wrote:
On 4/12/2019 11:15 PM, Joy Beeson wrote:


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


The hole causes what's called "stress concentration." That means when
there's a significant load on the stem, stresses will be higher in the
area right around the hole than they would have been without the hole.

Stress concentration is more of a problem for aluminum than for steel,
for reasons I won't go into here (unless asked). But it's not
necessarily a significant problem. Everyone accepts holes in aluminum
hubs (to attach spokes). I have holes drilled in my aluminum frame to
attach shift levers, bottle cages, etc. The problems arise only if the
concentrated stresses are higher than what the metal can resist for the
long term.

I gather from your posts that you're probably not a person who does lots
of high torque pedaling on sprints or tough climbs, where you're yanking
hard on the handlebars. Those yanks would put torque on the stem and
might generate some significant stress. But I doubt you'll see a problem.

More significant, perhaps, is that the hole is already there. If you
don't use the hole it doesn't improve the situation; it's still a stress
concentration. So leaving the cable out of the hole seems silly to me.

So I'd use it as intended. If you want to be super-diligent, check it
once a month to see if any tiny cracks are emanating from it. If you
want to be paranoid, replace the stem.


--
- Frank Krygowski


Her brake cable is already outside of the hole in the stem. Why should she have the housing shortened and all the work done to put the cable through the stem when braking won't be improved one iota but she'll have problems if in the future she wants to either raise or lower her stem?

Cheers


Looks better. Long ago there were shifter housings brazed onto the sides of downtubes. And you attached braze on shifters to them. And it looked good. But of course if you were scared of putting too much stress on the braze ons when shifting and causing your downtube to crack, you could also use clamp on shifters and have the braze ons act as stops for the clamps. Shifting would still be fine. But the look would be dumb.

Frank Krygowski[_4_] April 13th 19 08:14 PM

A hole in the stem
 
On 4/13/2019 2:00 PM, Sir Ridesalot wrote:
On Saturday, April 13, 2019 at 1:30:53 PM UTC-4, Frank Krygowski wrote:
On 4/12/2019 11:15 PM, Joy Beeson wrote:


I don't recall whether my handlebars came with the Raleigh Carleton or
the Fugi Grand Tourer -- we swapped components rather suddenly when a
mechanic overhauling the Raleigh found a defect in the brake bridge
that was above his pay grade. I don't think I ever knew whether the
handlebars and stems were included in the swap; we just left both
bikes with the mechanic.

It says "GB" in a circle in a recessed diamond on the stem.

Just above the point of the diamond, an adjusting barrel for the front
brake cable is set in the top of a hole through the stem.

I read somewhere that drilling a hole through the stem is a terrible,
horrible idea, and it makes sense that one should avoid weakening such
a vital component, but it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves.

So as long as the hole is there I might as well use it, but the
mechanic at the Trailhouse routes the cable around the stem, as if
there were no hole.

I'm going to have the bike overhauled pretty soon, and I'm thinking of
telling him to use the hole -- but is there some *other* reason why
routing a brale cable through the stem is a bad idea?


The hole causes what's called "stress concentration." That means when
there's a significant load on the stem, stresses will be higher in the
area right around the hole than they would have been without the hole.

Stress concentration is more of a problem for aluminum than for steel,
for reasons I won't go into here (unless asked). But it's not
necessarily a significant problem. Everyone accepts holes in aluminum
hubs (to attach spokes). I have holes drilled in my aluminum frame to
attach shift levers, bottle cages, etc. The problems arise only if the
concentrated stresses are higher than what the metal can resist for the
long term.

I gather from your posts that you're probably not a person who does lots
of high torque pedaling on sprints or tough climbs, where you're yanking
hard on the handlebars. Those yanks would put torque on the stem and
might generate some significant stress. But I doubt you'll see a problem.

More significant, perhaps, is that the hole is already there. If you
don't use the hole it doesn't improve the situation; it's still a stress
concentration. So leaving the cable out of the hole seems silly to me.

So I'd use it as intended. If you want to be super-diligent, check it
once a month to see if any tiny cracks are emanating from it. If you
want to be paranoid, replace the stem.


--
- Frank Krygowski


Her brake cable is already outside of the hole in the stem. Why should she have the housing shortened and all the work done to put the cable through the stem when braking won't be improved one iota but she'll have problems if in the future she wants to either raise or lower her stem?


Because, as Joy said: "it's a tempting idea: It looks neater, it
makes the path of the cable slightly smoother, and it makes the cable
a more convenient place to hang my gloves."

If she likes it, she should do it.

--
- Frank Krygowski


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