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Cup & Cone Bottom Brackets - Any Sources?



 
 
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  #11  
Old March 26th 08, 08:19 PM posted to rec.bicycles.tech
landotter
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Posts: 6,336
Default Cup & Cone Bottom Brackets - Any Sources?

On Mar 26, 1:48*pm, Hands Of Stone wrote:
On Mar 25, 6:09*am, landotter wrote:

On Mar 25, 6:29*am, Hands Of Stone wrote:


I am looking for a source for high-quality conventional cup & cone BBs
(JIS square taper). *Ritchey used to still make some but they are no
longer shown on his site. *Any ideas?


Any particular reason a cartridge BB won't work for you? FWIW--I
believe the new version house brand square taper BB at Nashbar is
being made by RPM in Taiwan and has an aluminum lock ring. Well made
and a steal at $15.


No, I have nothing against cartridge. *I just like everything about
the old-school BBs (except for the fixed cup): I run'em cageless with
a few extra balls, regrease and replace bearings (cheaply) when
needed, plus I like being able to adjust the bearings. *Why fix what
ain't broke? *Having said that, I may go with your idea as I am always
a sucker for a good deal.


It's a stupidly nice BB for the money. As much as I like loose ball
hubs and headsets, which are easy to maintain--I do love cartridge
BBs. I've never managed to wear one out--though the most miles I ever
put on one was 30K on a UN73. It's a superior technology, for sure.
Careful with the alloy cups, btw--you'll want to use loctite, these
guys like to work loose if assembled with grease.
Ads
  #12  
Old March 26th 08, 10:37 PM posted to rec.bicycles.tech
[email protected]
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Posts: 3,751
Default Cup & Cone Bottom Brackets - Any Sources?

landotter wrote:
On Mar 25, 6:29Â*am, Hands Of Stone wrote:
I am looking for a source for high-quality conventional cup & cone BBs
(JIS square taper). Â*Ritchey used to still make some but they are no
longer shown on his site. Â*Any ideas?



Any particular reason a cartridge BB won't work for you? FWIW--I
believe the new version house brand square taper BB at Nashbar is
being made by RPM in Taiwan and has an aluminum lock ring. Well made
and a steal at $15.



Jobst Brandt
  #13  
Old March 27th 08, 12:46 AM posted to rec.bicycles.tech
Donald Gillies
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Posts: 504
Default Cup & Cone Bottom Brackets - Any Sources?

datakoll writes:

try ... EPDI, ...


EPDI ?? The European Post Doctoral Institute ??

- Don Gillies
San Diego, CA, USA
  #14  
Old March 27th 08, 01:09 AM posted to rec.bicycles.tech
[email protected]
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Posts: 3,751
Default Cup & Cone Bottom Brackets - Any Sources?

The current design of the BBs one of the last holdovers from ancient
times that is still a perpetual problem. As I mentioned before, if it
has a left hand thread, the design is faulty, the thread being a crude
patch for the design problem, just as it is for pedal threads that
fail in spite of the orientation.

Left hand threads are used to cover for a moving interface that tends
to unscrews itself in use. As is visible on pedal crank faces, pedals
regardless of tightening, move in their contact with the crank and by
fretting erode the crank face. This erosion leads to cracks that
cause pedal eyes to fracture and throw the rider to the ground if
standing at the moment of failure.

Like pedals, BB cups also fret in the BB shell but, with the larger
thread, were moderately secure with right hand threads if tightened to
nearly unmanageable torque. That is why left hand threads are used
today to hide that they move. In time, the threads of the right hand
cup or BB shell become eroded to oblivion in time depending on which
of the two is the harder material. With steel hardened bearing cups,
the BB shell loses all its threads while with aluminum cups, the right
hand cup loses its threads.

Shimano has used a clamping method for left crank attachment to the
spindle that would also work for the BB. Meanwhile, cartridge
bearings fret on the inside and outside while the retaining cup frets
in the BB shell. That is what is wrong with the current design
especially with cartridge bearings.

In the short term, the current design works if monitored often and
maintained, but when the thread is gone, it presents a difficult
problem.

Jobst Brandt
  #15  
Old March 29th 08, 04:12 AM posted to rec.bicycles.tech
Tom Sherman[_2_]
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Posts: 9,890
Default Cup & Cone Bottom Brackets - Any Sources?

aka Jobst Brandt wrote:
The current design of the BBs one of the last holdovers from ancient
times that is still a perpetual problem. As I mentioned before, if it
has a left hand thread, the design is faulty, the thread being a crude
patch for the design problem, just as it is for pedal threads that
fail in spite of the orientation.

Left hand threads are used to cover for a moving interface that tends
to unscrews itself in use. As is visible on pedal crank faces, pedals
regardless of tightening, move in their contact with the crank and by
fretting erode the crank face. This erosion leads to cracks that
cause pedal eyes to fracture and throw the rider to the ground if
standing at the moment of failure.

Like pedals, BB cups also fret in the BB shell but, with the larger
thread, were moderately secure with right hand threads if tightened to
nearly unmanageable torque. That is why left hand threads are used
today to hide that they move. In time, the threads of the right hand
cup or BB shell become eroded to oblivion in time depending on which
of the two is the harder material. With steel hardened bearing cups,
the BB shell loses all its threads while with aluminum cups, the right
hand cup loses its threads.

Shimano has used a clamping method for left crank attachment to the
spindle that would also work for the BB. Meanwhile, cartridge
bearings fret on the inside and outside while the retaining cup frets
in the BB shell. That is what is wrong with the current design
especially with cartridge bearings.

In the short term, the current design works if monitored often and
maintained, but when the thread is gone, it presents a difficult
problem.

I just throw out the bicycle if I have problems with the bottom bracket.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
  #16  
Old March 29th 08, 04:29 AM posted to rec.bicycles.tech
[email protected]
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Posts: 3,751
Default Cup & Cone Bottom Brackets - Any Sources?

Tom Sherman wrote:

The current design of the BBs one of the last holdovers from
ancient times that is still a perpetual problem. As I mentioned
before, if it has a left hand thread, the design is faulty, the
thread being a crude patch for the design problem, just as it is
for pedal threads that fail in spite of the orientation.


Left hand threads are used to cover for a moving interface that
tends to unscrews itself in use. As is visible on pedal crank
faces, pedals regardless of tightening, move in their contact with
the crank and by fretting erode the crank face. This erosion leads
to cracks that cause pedal eyes to fracture and throw the rider to
the ground if standing at the moment of failure.


Like pedals, BB cups also fret in the BB shell but, with the larger
thread, were moderately secure with right hand threads if tightened
to nearly unmanageable torque. That is why left hand threads are
used today to hide that they move. In time, the threads of the
right hand cup or BB shell become eroded to oblivion in time
depending on which of the two is the harder material. With steel
hardened bearing cups, the BB shell loses all its threads while
with aluminum cups, the right hand cup loses its threads.


Shimano has used a clamping method for left crank attachment to the
spindle that would also work for the BB. Meanwhile, cartridge
bearings fret on the inside and outside while the retaining cup
frets in the BB shell. That is what is wrong with the current
design especially with cartridge bearings.


In the short term, the current design works if monitored often and
maintained, but when the thread is gone, it presents a difficult
problem.


I just throw out the bicycle if I have problems with the bottom
bracket.


In contrast, I had my involuntarily threadless BB bored out and a
hardened threaded steel sleeve silver soldered to keep my custom frame
of many years in service. I have a great frame builder and bikie
friend who has great metal working skills who also made the pedal
crank modification which solved the pedal to crank problem.

Jobst Brandt
  #17  
Old March 29th 08, 06:28 AM posted to rec.bicycles.tech
jim beam
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Posts: 5,758
Default Cup & Cone Bottom Brackets - Any Sources?

wrote:
Tom Sherman wrote:

The current design of the BBs one of the last holdovers from
ancient times that is still a perpetual problem. As I mentioned
before, if it has a left hand thread, the design is faulty, the
thread being a crude patch for the design problem, just as it is
for pedal threads that fail in spite of the orientation.


Left hand threads are used to cover for a moving interface that
tends to unscrews itself in use. As is visible on pedal crank
faces, pedals regardless of tightening, move in their contact with
the crank and by fretting erode the crank face. This erosion leads
to cracks that cause pedal eyes to fracture and throw the rider to
the ground if standing at the moment of failure.


Like pedals, BB cups also fret in the BB shell but, with the larger
thread, were moderately secure with right hand threads if tightened
to nearly unmanageable torque. That is why left hand threads are
used today to hide that they move. In time, the threads of the
right hand cup or BB shell become eroded to oblivion in time
depending on which of the two is the harder material. With steel
hardened bearing cups, the BB shell loses all its threads while
with aluminum cups, the right hand cup loses its threads.


Shimano has used a clamping method for left crank attachment to the
spindle that would also work for the BB. Meanwhile, cartridge
bearings fret on the inside and outside while the retaining cup
frets in the BB shell. That is what is wrong with the current
design especially with cartridge bearings.


In the short term, the current design works if monitored often and
maintained, but when the thread is gone, it presents a difficult
problem.


I just throw out the bicycle if I have problems with the bottom
bracket.


In contrast, I had my involuntarily threadless BB bored out and a
hardened threaded steel sleeve silver soldered to keep my custom frame
of many years in service.


otoh, by not simply replacing a worn out frame, you're deliberately
avoiding bothering to research improvements in frame design such as
over-size tube which help mitigate shimmy. or aluminum. or carbon. as
someone that like to express opinion on these materials, the least you
should do is bother to actually use them.


I have a great frame builder and bikie
friend who has great metal working skills who also made the pedal
crank modification which solved the pedal to crank problem.


what "crank problem" is that? when is the last time you saw pedal eye
breakage on an "unmodified" crank?
  #18  
Old March 29th 08, 06:36 AM posted to rec.bicycles.tech
Tom Sherman[_2_]
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Posts: 9,890
Default Cup & Cone Bottom Brackets - Any Sources?

"jim beam" wrote:
[...]
otoh, by not simply replacing a worn out frame, you're deliberately
avoiding bothering to research improvements in frame design such as
over-size tube which help mitigate shimmy. or aluminum.


Aluminium makes for a very poor frame. Aluminium alloy with proper heat
treatment can make a perfectly fine frame however.

or carbon.


Just carbon? Is this a diamond frame (pun intended)?

as
someone that like to express opinion on these materials, the least you
should do is bother to actually use them.

One would think a former materials scientist would be more precise in
terminology. Even a "lightweight" knows better.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
  #19  
Old March 29th 08, 04:50 PM posted to rec.bicycles.tech
datakoll
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Posts: 7,793
Default Cup & Cone Bottom Brackets - Any Sources?

On Mar 26, 7:46*pm, (Donald Gillies) wrote:
datakoll writes:

try ... *EPDI, ...


EPDI ?? *The European Post Doctoral Institute ??

- Don Gillies
San Diego, CA, USA


EPDI stocks EOM Shimano back to year one. They're in Bakersfield
  #20  
Old March 29th 08, 08:20 PM posted to rec.bicycles.tech
Hank
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Posts: 887
Default Cup & Cone Bottom Brackets - Any Sources?

On Mar 28, 10:28 pm, jim beam wrote:
wrote:
Tom Sherman wrote:


The current design of the BBs one of the last holdovers from
ancient times that is still a perpetual problem. As I mentioned
before, if it has a left hand thread, the design is faulty, the
thread being a crude patch for the design problem, just as it is
for pedal threads that fail in spite of the orientation.


Left hand threads are used to cover for a moving interface that
tends to unscrews itself in use. As is visible on pedal crank
faces, pedals regardless of tightening, move in their contact with
the crank and by fretting erode the crank face. This erosion leads
to cracks that cause pedal eyes to fracture and throw the rider to
the ground if standing at the moment of failure.


Like pedals, BB cups also fret in the BB shell but, with the larger
thread, were moderately secure with right hand threads if tightened
to nearly unmanageable torque. That is why left hand threads are
used today to hide that they move. In time, the threads of the
right hand cup or BB shell become eroded to oblivion in time
depending on which of the two is the harder material. With steel
hardened bearing cups, the BB shell loses all its threads while
with aluminum cups, the right hand cup loses its threads.


Shimano has used a clamping method for left crank attachment to the
spindle that would also work for the BB. Meanwhile, cartridge
bearings fret on the inside and outside while the retaining cup
frets in the BB shell. That is what is wrong with the current
design especially with cartridge bearings.


In the short term, the current design works if monitored often and
maintained, but when the thread is gone, it presents a difficult
problem.


I just throw out the bicycle if I have problems with the bottom
bracket.


In contrast, I had my involuntarily threadless BB bored out and a
hardened threaded steel sleeve silver soldered to keep my custom frame
of many years in service.


otoh, by not simply replacing a worn out frame, you're deliberately
avoiding bothering to research improvements in frame design such as
over-size tube which help mitigate shimmy. or aluminum. or carbon. as
someone that like to express opinion on these materials, the least you
should do is bother to actually use them.

I have a great frame builder and bikie
friend who has great metal working skills who also made the pedal
crank modification which solved the pedal to crank problem.


what "crank problem" is that? when is the last time you saw pedal eye
breakage on an "unmodified" crank?


For me, it was about a year ago - at least, a significant crack that I
caught (by sound, which is saying something, because I'm hard of
hearing) before it broke, on a 9-speed Veloce LH arm.
 




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