Bent Axles

"W. Stief" wrote
Recently acqired 3 used up bikes for rebuild/ restore.
Bianchi tourer Sturmy 3 spd needs parts (all), just braggin.)
NEXT and Giant both have 10mm? axles bent, 3x9 Shimano on the Giant
as I
recall 3x9 something on the NEXT beater.
OK, I weigh 180 lbs. and ride rough - some curb jumping, pavement.
The axles were bent before I got them, straightened fairly good but
not
right.
In fact the Giant has a race dinged, probably from lack of grease,
alignment.
I see various axle material offered.
Is plain steel best axles for these old bikes or would titanium be
stronger?
Thanks for looking.
Yes, I found all the bearing balls for the freewheels and put them
back, PITA

* * Chas wrote:
Ever hear the phrase "silk stockings on a rooster" or "silk purse out
of a..." never mind (referring to titanium axles). 8-)
The 9mm axles are almost always found on inexpensive nutted hubs.
Quick
release front hubs are usually 9.5mm, same thing with better quality
nutted axles. Better quality rear axles whether nutted or quick
release
are usually 10mm diameter.
There is a good chance that the rims and spokes on you wheels will be
prone to breakage also.

My suggestion is find some better quality new or used wheels with more
robust axles. If you are going to be jumping and riding over curbs
etc.
you'll always be bending rear axles with cheap wheels (it takes a lot
more to bend front axles).
As Jobst pointed out most bent axles will have cracks in them and will
eventually fail. Cheap hubs use cheap low strength steel in the axles.
Better quality steel axles will still bend but they will be stronger
and have more resistance to failure.

"A Muzi" wrote
Standard grade nutted axles are traditionally 8mm front with 9.5mm
rear.
(modern rears, after about 1995, are often 10mm)

QR axles are 9mm front and 10mm rear, as are track axles.
Exceptions abound of course.

* * Chas wrote:
You and Chalo are both correct on the dimensions except the ISO standard
front is 9mm.
A. I haven't worked on anything but better quality hubs in years i.e.
Campy, Shimano and Maillard etc.
B. Figured out years ago that cheap hubs weren't worth repairing because
of bent or broken axles, worn out cones and cracked or otherwise damaged
cups. This was the gist of my primary comments. You could buy better
quality replacement wheels for less time and money than it usually
took to
repair a cheap hub which generally had cheap spokes and rims.

A Muzi wrote:
For some values of 'cheap' I suppose.

You're right about Excel, Weco and that sort of thing but a standard
grade Normandy/Atom or Suzue or Shimano for that matter is quite
durable, given a shot of lube and a reasonable adjustment when new and
occasional rebuild. The Normandy track hub on my fixie has seen 14
winters of daily riding and I was given that the wheel used. That is
not an unusual experience from what I see on our customers' bikes.
Standard grade hubs often show a smooth bearing surface effectively
polished by miles. Even a medium quality to expensive hub, if put in
service factory-tight without grease, will go suicidal.

jim beam wrote:
but here's the conundrum with "factory-tight" from the manufacturer
viewpoint: the first usage the hub gets is during wheel building. and
for that operation, if you want the wheel to be true, the bearings need
to be snug. after that, the bearings can be slacked off to compensate
for application, especially with qr's. but again, from a manufacturer
viewpoint, you really can't ship a hub with anything other than snug
bearings. [helps mitigate risk of false brinelling during
transportation too.]

You're exactly right on that. We agree the manufacturer is not 'at
fault' just because it's delivered tight and/or unlubricated. Final
prep, or it's omission, is an oft-overlooked aspect of hub failure.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

A Muzi wrote:
"W. Stief" wrote
Recently acqired 3 used up bikes for rebuild/ restore.
Bianchi tourer Sturmy 3 spd needs parts (all), just braggin.)
NEXT and Giant both have 10mm? axles bent, 3x9 Shimano on the Giant
as I
recall 3x9 something on the NEXT beater.
OK, I weigh 180 lbs. and ride rough - some curb jumping, pavement.
The axles were bent before I got them, straightened fairly good but
not
right.
In fact the Giant has a race dinged, probably from lack of grease,
alignment.
I see various axle material offered.
Is plain steel best axles for these old bikes or would titanium be
stronger?
Thanks for looking.
Yes, I found all the bearing balls for the freewheels and put them
back, PITA

* * Chas wrote:
Ever hear the phrase "silk stockings on a rooster" or "silk purse out
of a..." never mind (referring to titanium axles). 8-)
The 9mm axles are almost always found on inexpensive nutted hubs.
Quick
release front hubs are usually 9.5mm, same thing with better quality
nutted axles. Better quality rear axles whether nutted or quick
release
are usually 10mm diameter.
There is a good chance that the rims and spokes on you wheels will be
prone to breakage also.

My suggestion is find some better quality new or used wheels with
more
robust axles. If you are going to be jumping and riding over curbs
etc.
you'll always be bending rear axles with cheap wheels (it takes a lot
more to bend front axles).
As Jobst pointed out most bent axles will have cracks in them and
will
eventually fail. Cheap hubs use cheap low strength steel in the
axles.
Better quality steel axles will still bend but they will be stronger
and have more resistance to failure.

"A Muzi" wrote
Standard grade nutted axles are traditionally 8mm front with 9.5mm
rear.
(modern rears, after about 1995, are often 10mm)

QR axles are 9mm front and 10mm rear, as are track axles.
Exceptions abound of course.

* * Chas wrote:
You and Chalo are both correct on the dimensions except the ISO
standard
front is 9mm.
A. I haven't worked on anything but better quality hubs in years i.e.
Campy, Shimano and Maillard etc.
B. Figured out years ago that cheap hubs weren't worth repairing
because
of bent or broken axles, worn out cones and cracked or otherwise
damaged
cups. This was the gist of my primary comments. You could buy better
quality replacement wheels for less time and money than it usually
took to
repair a cheap hub which generally had cheap spokes and rims.

A Muzi wrote:
For some values of 'cheap' I suppose.

You're right about Excel, Weco and that sort of thing but a standard
grade Normandy/Atom or Suzue or Shimano for that matter is quite
durable, given a shot of lube and a reasonable adjustment when new
and occasional rebuild. The Normandy track hub on my fixie has seen
14 winters of daily riding and I was given that the wheel used. That
is not an unusual experience from what I see on our customers' bikes.
Standard grade hubs often show a smooth bearing surface effectively
polished by miles. Even a medium quality to expensive hub, if put in
service factory-tight without grease, will go suicidal.

jim beam wrote:
but here's the conundrum with "factory-tight" from the manufacturer
viewpoint: the first usage the hub gets is during wheel building. and
for that operation, if you want the wheel to be true, the bearings
need to be snug. after that, the bearings can be slacked off to
compensate for application, especially with qr's. but again, from a
manufacturer viewpoint, you really can't ship a hub with anything
other than snug bearings. [helps mitigate risk of false brinelling
during transportation too.]

You're exactly right on that. We agree the manufacturer is not 'at
fault' just because it's delivered tight and/or unlubricated.

"unlubricated" is highly subjective. grease doesn't "flow" in a
bearing, so anything that's not actually in the raceway or on a bearing
ball is superfluous. i know people here like to lay it on thick, but
really, it's almost all wasted since only the merest fraction is
actually ever used.


Final
prep, or it's omission, is an oft-overlooked aspect of hub failure.

jim beam wrote:

A Muzi wrote:

We agree the manufacturer is not 'at
fault' just because it's delivered tight and/or unlubricated. *

"unlubricated" is highly subjective. *grease doesn't "flow" in a
bearing, so anything that's not actually in the raceway or on a bearing
ball is superfluous. *i know people here like to lay it on thick, but
really, it's almost all wasted since only the merest fraction is
actually ever used.

Plentiful grease can build up in berms such that the balls
occasionally entrain fresh grease back into the raceway. I have never
seen an adequately greased bearing display dry balls and races upon
opening (caked with filth, perhaps, but not dry), but I have seen it
time and again with hubs that had been put into service as supplied
from the manufacturer.

"Excess" bearing grease serves other purposes, as a supplemental
barrier to contaminants and an anti-corrosion coating. I know what
Jobst says about the grease lip being able to introduce contamination
into a sealed cartridge bearing, but in my observation bearings with
complete fill of grease go longer before needing service than bearings
with a scant fill.

Chalo

"Chalo" wrote in message
...
jim beam wrote:

A Muzi wrote:

We agree the manufacturer is not 'at
fault' just because it's delivered tight and/or unlubricated.

"unlubricated" is highly subjective. grease doesn't "flow" in a
bearing, so anything that's not actually in the raceway or on a bearing
ball is superfluous. i know people here like to lay it on thick, but
really, it's almost all wasted since only the merest fraction is
actually ever used.

Plentiful grease can build up in berms such that the balls
occasionally entrain fresh grease back into the raceway. I have never
seen an adequately greased bearing display dry balls and races upon
opening (caked with filth, perhaps, but not dry), but I have seen it
time and again with hubs that had been put into service as supplied
from the manufacturer.

"Excess" bearing grease serves other purposes, as a supplemental
barrier to contaminants and an anti-corrosion coating. I know what
Jobst says about the grease lip being able to introduce contamination
into a sealed cartridge bearing, but in my observation bearings with
complete fill of grease go longer before needing service than bearings
with a scant fill.

Chalo

I agree with you about extra grease providing a barrier against
contaminants. In the desert Southwest part of the US sand entering the
bearings was one of the biggest causes of bearing failure. We used very
high viscosity "fiber" grease designed for automotive wheel bearings. It
remained thick and didn't soften and run out from heat exposure when bikes
sat in direct sunlight. We also experimented with barrier seals made with
pipe cleaners or rubber O-rings on the hub and BB axles.

In high speed applications such as automotive wheel bearings or greased
bearings in machinery, as the grease breaks down and heat increases, extra
grease in the bearing "melts" and flows into the bearing surfaces. Bicycle
bearings rarely develop that kind of heat so I agree with Andrew's point
about the amount of grease in the ball surfaces.

Chas.

* * Chas wrote:
"Chalo" wrote in message
...
jim beam wrote:
A Muzi wrote:
We agree the manufacturer is not 'at
fault' just because it's delivered tight and/or unlubricated.
"unlubricated" is highly subjective. grease doesn't "flow" in a
bearing, so anything that's not actually in the raceway or on a bearing
ball is superfluous. i know people here like to lay it on thick, but
really, it's almost all wasted since only the merest fraction is
actually ever used.

Plentiful grease can build up in berms such that the balls
occasionally entrain fresh grease back into the raceway. I have never
seen an adequately greased bearing display dry balls and races upon
opening (caked with filth, perhaps, but not dry), but I have seen it
time and again with hubs that had been put into service as supplied
from the manufacturer.

"Excess" bearing grease serves other purposes, as a supplemental
barrier to contaminants and an anti-corrosion coating. I know what
Jobst says about the grease lip being able to introduce contamination
into a sealed cartridge bearing, but in my observation bearings with
complete fill of grease go longer before needing service than bearings
with a scant fill.

Chalo

I agree with you about extra grease providing a barrier against
contaminants. In the desert Southwest part of the US sand entering the
bearings was one of the biggest causes of bearing failure. We used very
high viscosity "fiber" grease designed for automotive wheel bearings. It
remained thick and didn't soften and run out from heat exposure when bikes
sat in direct sunlight. We also experimented with barrier seals made with
pipe cleaners or rubber O-rings on the hub and BB axles.

In high speed applications such as automotive wheel bearings or greased
bearings in machinery, as the grease breaks down and heat increases, extra
grease in the bearing "melts" and flows into the bearing surfaces. Bicycle
bearings rarely develop that kind of heat so I agree with Andrew's point
about the amount of grease in the ball surfaces.

Chas.



high temperature is the one instance where it /can/ make a difference
because these's the chance grease /can/ flow. doesn't happen at andy
muzi winter temperatures though.