Fixed pedal spindle - put the bearing in the crank

http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. It seems to be
addressing the issue of the left-handed threaded left spindle.

If I recall, Jobst has repeatedly pointed out that one could simply use
the same solution as the automobile industry. I'm curious what
everyone's take on this is.

My summary: the bottom of the crank has a cartridge bearing in it. A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.

\\paul
--
Paul M. Hobson
..:change the f to ph to reply:.

Paul M. Hobson wrote:

http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. *It seems to be
addressing the issue of the left-handed threaded left spindle.

If I recall, Jobst has repeatedly pointed out that one could simply use
the same solution as the automobile industry. *I'm curious what
everyone's take on this is.

My summary: the bottom of the crank has a cartridge bearing in it. *A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.

That's a whole lot like the long-departed Shimano AX pedal system,
which was... problematic.

It's also a lot to ask of a li'l old lonely ball bearing.

Chalo

On Tue, 15 Jul 2008 23:49:40 -0700
"Paul M. Hobson" wrote:

http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. It seems to be
addressing the issue of the left-handed threaded left spindle.

If I recall, Jobst has repeatedly pointed out that one could simply
use the same solution as the automobile industry. I'm curious what
everyone's take on this is.

My summary: the bottom of the crank has a cartridge bearing in it. A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.

\\paul

All the force is outboard of the bearing. It won't last.

What's wrong with left-hand threading the left pedal?

Cheers

Joel
--
Human Powered Cycles | High quality servicing and repairs
| Affordable second hand bikes
(03) 9029 6504 | Commuting and touring parts and accessories
www.humanpowered.com.au | Mechanical and on-road training and
instruction

On Tue, 15 Jul 2008 23:49:40 -0700
"Paul M. Hobson" wrote:

http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. It seems to be
addressing the issue of the left-handed threaded left spindle.

If I recall, Jobst has repeatedly pointed out that one could simply
use the same solution as the automobile industry. I'm curious what
everyone's take on this is.

My summary: the bottom of the crank has a cartridge bearing in it. A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.

Joel Mayes wrote:
All the force is outboard of the bearing. It won't last.

What's wrong with left-hand threading the left pedal?

I don't particularly have a problem with it. But this is from the JB FAQ:
|Left hand threads would not be required on left pedals if a design
|common on cars were used. Before the advent of conical lug nuts, many
|cars used left hand threads on left side wheels. Today, stories of
|wheels rolling away from cars no longer make news, the conical seat
|having solved this problem on car wheels as it could on bicycle pedals.
|
|However, unscrewing is not the main problem for pedals, but rather
|crank failure caused by fretting erosion of the pedal eye. Fretting
|initiates cracks that can cause sudden and unsuspected pedal separation
|when the eye of a crank breaks. Because this occurs equally with right
|and left cranks it is the more important reason for a conical spindle
|face and crank eye. This has been tested.

http://sheldonbrown.com/brandt/left.html

--
Paul M. Hobson
..:change the f to ph to reply:.

On Jul 16, 10:27*am, "Paul M. Hobson" wrote:
On Tue, 15 Jul 2008 23:49:40 -0700
"Paul M. Hobson" wrote:

http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. *It seems to be
addressing the issue of the left-handed threaded left spindle.

If I recall, Jobst has repeatedly pointed out that one could simply
use the same solution as the automobile industry. *I'm curious what
everyone's take on this is.

My summary: the bottom of the crank has a cartridge bearing in it. *A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.
Joel Mayes wrote:
All the force is outboard of the bearing. It won't last.

What's wrong with left-hand threading the left pedal?

I don't particularly have a problem with it. *But this is from the JB FAQ:
|Left hand threads would not be required on left pedals if a design
|common on cars were used. Before the advent of conical lug nuts, many
|cars used left hand threads on left side wheels. Today, stories of
|wheels rolling away from cars no longer make news, the conical seat
|having solved this problem on car wheels as it could on bicycle pedals.
|
|However, unscrewing is not the main problem for pedals, but rather
|crank failure caused by fretting erosion of the pedal eye. Fretting
|initiates cracks that can cause sudden and unsuspected pedal separation
|when the eye of a crank breaks. Because this occurs equally with right
|and left cranks it is the more important reason for a conical spindle
|face and crank eye. This has been tested.

http://sheldonbrown.com/brandt/left.html

--
Paul M. Hobson
.:change the f to ph to reply:.- Hide quoted text -

- Show quoted text -

it's a way of selling pedal and crank combo, only a fool like ozark
bicycle would be interested

On Jul 15, 11:49 pm, "Paul M. Hobson" wrote:
http://tinyurl.com/fixed-pedal-spindle

The link above is to a new Crank Bros pedal patent. It seems to be
addressing the issue of the left-handed threaded left spindle.

The patent lists several advantages that have nothing to do
with the thread direction: fewer parts, ease of replacing
the bearing, low stack height, ...

(I'm not commenting on whether it's a practical idea overall; I'm only
saying the stated motivation wasn't to deal with the thread
direction.)


My favorite sentence in the patent:

"For pedals that use loose ball bearings rather than cartridge
bearings or bushings, it is easy to lose the balls during
disassembly, and nearly impossible to reassemble the balls
and properly adjust the bearings."

'Nearly impossible'. Heh.


Tom Ace

Paul M. Hobson wrote:
http://tinyurl.com/fixed-pedal-spindle
The link above is to a new Crank Bros pedal patent. It seems to be
addressing the issue of the left-handed threaded left spindle.
If I recall, Jobst has repeatedly pointed out that one could simply use
the same solution as the automobile industry. I'm curious what
everyone's take on this is.
My summary: the bottom of the crank has a cartridge bearing in it. A
pedal with a fixed hollow spindle slides in and is secured with a
threaded bolt from the other side.

Chalo wrote:
That's a whole lot like the long-departed Shimano AX pedal system,
which was... problematic.
It's also a lot to ask of a li'l old lonely ball bearing.

There's that, although the Shimano system did not exhibit many bearing
or crank problems. It was more a social engineering issue - we sell a
case of MKS touring pedals a month to replace the clipless pedals which
customers do not like on their new bikes. If this is going to fly,
somebody needs to make a toeclip-compatible or sneaker-compatible pedal.

The crank as drawn is pretty darned thin around the bearing -production
models can't possibly be that wimpy.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

On Jul 16, 2:02*pm, A Muzi wrote:


The crank as drawn is pretty darned thin around the bearing -production
models can't possibly be that wimpy.
--
Andrew Muzi
* www.yellowjersey.org/
* Open every day since 1 April, 1971
** Posted fromhttp://www.teranews.com**

darned right, that's the critical flaw in the whole thing

A Muzi wrote:

customers do not like on their new bikes. If this is going to fly,
somebody needs to make a toeclip-compatible or sneaker-compatible pedal.

Figure 6 appears to display a platform pedal, so apparently they're
considering it.


--
Work and recreation are not often effected at the same time.
One using a bicycle in business makes an exception to the rule.
- Dr. Edgar H. Earl, Rochester. (~1892)

Andrew Muzi wrote:
...It was more a social engineering issue - we sell a
case of MKS touring pedals a month to replace the clipless pedals which
customers do not like on their new bikes....

Some cheeseheads, er people, are weird.

--
Tom Sherman - Holstein-Friesland Bovinia
"People who had no mercy will find none." - Anon.