Sealed Bearings

On 06/06/16 06:58, Ian Field wrote:


"James" wrote in message
...
On 06/06/16 05:09, Ian Field wrote:


"James" wrote in message
...
On 05/06/16 06:20, Ian Field wrote:


"James" wrote in message
...
On 04/06/16 12:25, John B. wrote:


Frankly, I can't tell the difference between seals and no seals :-)


My headlight is driven by my front dynamo hub. I can't feel a
difference in drag when I switch between light on and light off,

When I had an old Sturmey-Archer hub dynamo, I could feel it "cogging"
at very low speed.


The cogging feeling does not necessarily mean drag.

Never said it did - I was making the point that very slight influences
could be perceptible.

Never claimed you said it did - I was also making a point.

Is *EVERYONE* on this group capable of starting an argument in an empty
room?!!!!!



There is no need to shout, Ian. How rude.

--
JS

On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
news
On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James
wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB that is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing. All of
the seals I've seen are rubber, and they most certainly do not "burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time ago, to
find out what they estimate bearing loses to be for a typical double
sealed cartridge bearing as used in the wheels I had at the time. The
bearings have a rubber seal on both sides. If I remember correctly,
the
loses per bearing were in the order of 0.5W at a road speed of 50km/h.
0.1W of that was rolling friction. I.e. sticky grease and friction in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to raise
the
bearing temperature by some detectible level above ambient - even if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of wheels
with cartridge bearings and before I built the wheels I took the hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides - it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember seeing an
advert for a grease gun/ram device you clamp metal shield bearings into to
force grease in - if you try that with a seal bearing; the seal pops out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil? After all, an oil bath would not only ensure
cleanliness but also provide better lubrication and serve to cool the
bearing.

Please note, I was referring to someone with normal intelligence.
--
cheers,

John B.

On Mon, 6 Jun 2016 07:25:54 +1000, James
wrote:

On 06/06/16 06:58, Ian Field wrote:


"James" wrote in message
...
On 06/06/16 05:09, Ian Field wrote:


"James" wrote in message
...
On 05/06/16 06:20, Ian Field wrote:


"James" wrote in message
...
On 04/06/16 12:25, John B. wrote:


Frankly, I can't tell the difference between seals and no seals :-)


My headlight is driven by my front dynamo hub. I can't feel a
difference in drag when I switch between light on and light off,

When I had an old Sturmey-Archer hub dynamo, I could feel it "cogging"
at very low speed.


The cogging feeling does not necessarily mean drag.

Never said it did - I was making the point that very slight influences
could be perceptible.

Never claimed you said it did - I was also making a point.

Is *EVERYONE* on this group capable of starting an argument in an empty
room?!!!!!



There is no need to shout, Ian. How rude.

Cheer up, he hasn't called you a "****wit" yet.....
--
cheers,

John B.

"John B." wrote in message
...
On Mon, 6 Jun 2016 07:25:54 +1000, James
wrote:

On 06/06/16 06:58, Ian Field wrote:


"James" wrote in message
...
On 06/06/16 05:09, Ian Field wrote:


"James" wrote in message
...
On 05/06/16 06:20, Ian Field wrote:


"James" wrote in message
...
On 04/06/16 12:25, John B. wrote:


Frankly, I can't tell the difference between seals and no seals
:-)


My headlight is driven by my front dynamo hub. I can't feel a
difference in drag when I switch between light on and light off,

When I had an old Sturmey-Archer hub dynamo, I could feel it
"cogging"
at very low speed.


The cogging feeling does not necessarily mean drag.

Never said it did - I was making the point that very slight influences
could be perceptible.

Never claimed you said it did - I was also making a point.

Is *EVERYONE* on this group capable of starting an argument in an empty
room?!!!!!



There is no need to shout, Ian. How rude.

Cheer up, he hasn't called you a "****wit" yet.....

It pretty much applies to anyone who thinks you're
not..............................

"John B." wrote in message
...
On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
news
On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James
wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB that is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing. All
of
the seals I've seen are rubber, and they most certainly do not "burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time ago,
to
find out what they estimate bearing loses to be for a typical double
sealed cartridge bearing as used in the wheels I had at the time.
The
bearings have a rubber seal on both sides. If I remember correctly,
the
loses per bearing were in the order of 0.5W at a road speed of
50km/h.
0.1W of that was rolling friction. I.e. sticky grease and friction
in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to raise
the
bearing temperature by some detectible level above ambient - even if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of wheels
with cartridge bearings and before I built the wheels I took the hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides - it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember seeing
an
advert for a grease gun/ram device you clamp metal shield bearings into
to
force grease in - if you try that with a seal bearing; the seal pops
out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil?

I never said they did - but in a desperate attempt to rescue you from your
state of confusion; bearings with a seal one side are routinely used for
shafts emerging through the casing of an oil immersion sump.

Your continuing deterioration makes explaining it to you difficult, so I'll
explain it in simple terms for you; seal bearings have rubber seals, shield
bearings have metal shields.

You probably still need someone to draw pictures for you - but this isn't a
binaries group.

On Mon, 6 Jun 2016 19:05:22 +0100, "Ian Field"
wrote:



"John B." wrote in message
.. .
On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
news On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James
wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB that is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing. All
of
the seals I've seen are rubber, and they most certainly do not "burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time ago,
to
find out what they estimate bearing loses to be for a typical double
sealed cartridge bearing as used in the wheels I had at the time.
The
bearings have a rubber seal on both sides. If I remember correctly,
the
loses per bearing were in the order of 0.5W at a road speed of
50km/h.
0.1W of that was rolling friction. I.e. sticky grease and friction
in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to raise
the
bearing temperature by some detectible level above ambient - even if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of wheels
with cartridge bearings and before I built the wheels I took the hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides - it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember seeing
an
advert for a grease gun/ram device you clamp metal shield bearings into
to
force grease in - if you try that with a seal bearing; the seal pops
out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil?

I never said they did - but in a desperate attempt to rescue you from your
state of confusion; bearings with a seal one side are routinely used for
shafts emerging through the casing of an oil immersion sump.

In fact you did say. You said "If they run immersed in oil, then no
problem", if you have forgotten see above.

I simply asked why would anyone select sealed bearings to use immersed
in oil?

Your continuing deterioration makes explaining it to you difficult, so I'll
explain it in simple terms for you; seal bearings have rubber seals, shield
bearings have metal shields.

You probably still need someone to draw pictures for you - but this isn't a
binaries group.

Perhaps, but then you might answer my question as to why would one
select a sealed bearing to run "immersed in oil", which would
eliminate the requirement for pictures.
--
cheers,

John B.

"John B." wrote in message
news
On Mon, 6 Jun 2016 19:05:22 +0100, "Ian Field"
wrote:



"John B." wrote in message
. ..
On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
news On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James

wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB that
is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing. All
of
the seals I've seen are rubber, and they most certainly do not
"burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow
than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time
ago,
to
find out what they estimate bearing loses to be for a typical
double
sealed cartridge bearing as used in the wheels I had at the time.
The
bearings have a rubber seal on both sides. If I remember
correctly,
the
loses per bearing were in the order of 0.5W at a road speed of
50km/h.
0.1W of that was rolling friction. I.e. sticky grease and
friction
in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to
raise
the
bearing temperature by some detectible level above ambient - even
if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of
wheels
with cartridge bearings and before I built the wheels I took the
hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides - it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember
seeing
an
advert for a grease gun/ram device you clamp metal shield bearings
into
to
force grease in - if you try that with a seal bearing; the seal pops
out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil?

I never said they did - but in a desperate attempt to rescue you from your
state of confusion; bearings with a seal one side are routinely used for
shafts emerging through the casing of an oil immersion sump.

In fact you did say. You said "If they run immersed in oil, then no
problem", if you have forgotten see above.

In the same sentence as I mentioned shield bearings - its really hard to
comprehend just how thick you are!!!

On Tue, 7 Jun 2016 19:08:12 +0100, "Ian Field"
wrote:



"John B." wrote in message
news
On Mon, 6 Jun 2016 19:05:22 +0100, "Ian Field"
wrote:



"John B." wrote in message
...
On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
news On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James

wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB that
is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing. All
of
the seals I've seen are rubber, and they most certainly do not
"burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow
than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time
ago,
to
find out what they estimate bearing loses to be for a typical
double
sealed cartridge bearing as used in the wheels I had at the time.
The
bearings have a rubber seal on both sides. If I remember
correctly,
the
loses per bearing were in the order of 0.5W at a road speed of
50km/h.
0.1W of that was rolling friction. I.e. sticky grease and
friction
in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to
raise
the
bearing temperature by some detectible level above ambient - even
if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of
wheels
with cartridge bearings and before I built the wheels I took the
hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides - it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember
seeing
an
advert for a grease gun/ram device you clamp metal shield bearings
into
to
force grease in - if you try that with a seal bearing; the seal pops
out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil?

I never said they did - but in a desperate attempt to rescue you from your
state of confusion; bearings with a seal one side are routinely used for
shafts emerging through the casing of an oil immersion sump.

In fact you did say. You said "If they run immersed in oil, then no
problem", if you have forgotten see above.

In the same sentence as I mentioned shield bearings - its really hard to
comprehend just how thick you are!!!

Given that your memory appears to be faulty I remind you that actually
you wrote: "Bearings with metal shield on one or both sides aren't
exactly rare though. If they run immersed in oil, then no problem."

Please note the capital letters beginning the sentences and the
periods ending them.

And, I asked, "Again, why would anyone use a sealed bearing in a
system where it was immersed in oil."

And apparently from your responses to date, you either can't
understand the question or you lack the knowledge to reply.
--
cheers,

John B.

"John B." wrote in message
...
On Tue, 7 Jun 2016 19:08:12 +0100, "Ian Field"
wrote:



"John B." wrote in message
news
On Mon, 6 Jun 2016 19:05:22 +0100, "Ian Field"
wrote:



"John B." wrote in message
m...
On Sun, 5 Jun 2016 20:13:58 +0100, "Ian Field"
wrote:



"John B." wrote in message
newsod7lbh6pv9cvhjd6jjkmjcb3rabrpbh9e@4ax. com...
On Sat, 4 Jun 2016 21:14:45 +0100, "Ian Field"
wrote:



"James" wrote in message
...
On 03/06/16 19:55, John B. wrote:
On Fri, 3 Jun 2016 14:28:29 +1000, James

wrote:

On 03/06/16 03:40, Joerg wrote:



I was thinking about the material used in the seals. On MTB
that
is
usually rubber and on road bikes often some sort of fiber. Very
small,
so the seal itself would likely burn up.



I have never seen a fibre "seal" used on any bicycle bearing.
All
of
the seals I've seen are rubber, and they most certainly do not
"burn
up".


It has more surface area than heat sinks used for integrated
circuits
which need to dissipate tens of watts, and FAR better airflow
than
you
find inside most electronic equipment as well.

And 2% of 200 is 4, by the way.


But you have four bearings, so 1W each.


I used an on line estimator of bearing losses by SKF some time
ago,
to
find out what they estimate bearing loses to be for a typical
double
sealed cartridge bearing as used in the wheels I had at the
time.
The
bearings have a rubber seal on both sides. If I remember
correctly,
the
loses per bearing were in the order of 0.5W at a road speed of
50km/h.
0.1W of that was rolling friction. I.e. sticky grease and
friction
in
the ball cage. 0.4W was from the seal friction.

So a total of about 1W per wheel at 50km/h. Hardly enough to
raise
the
bearing temperature by some detectible level above ambient -
even
if
the
bike was stationary and being pedalled on rollers!

Could you have used "seal one side" bearings. I have a set of
wheels
with cartridge bearings and before I built the wheels I took the
hubs
apart and that is what they had. So (I guess) only 1/2W at 50 :-)


Could have of course. Makes no difference to me.

Can't remember ever having seen a bearing with a seal both sides -
it
could
only ever be lubricated during manufacture, then you're stuck with
whatever
they put in it.

See: http://www.engineerstudent.co.uk/bea...explained.html

Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem. I vaguely remember
seeing
an
advert for a grease gun/ram device you clamp metal shield bearings
into
to
force grease in - if you try that with a seal bearing; the seal pops
out.

Why would a bearing immersed in oil require a seal?

Once again you demonstrate your astounding lack of reading
comprehension.........................

"Bearings with metal shield on one or both sides aren't exactly rare
though.
If they run immersed in oil, then no problem.".

Again, why would anyone use a sealed bearing in a system where it was
immersed in oil?

I never said they did - but in a desperate attempt to rescue you from
your
state of confusion; bearings with a seal one side are routinely used for
shafts emerging through the casing of an oil immersion sump.

In fact you did say. You said "If they run immersed in oil, then no
problem", if you have forgotten see above.

In the same sentence as I mentioned shield bearings - its really hard to
comprehend just how thick you are!!!

Given that your memory appears to be faulty I remind you that actually
you wrote: "Bearings with metal shield on one or both sides aren't
exactly rare though. If they run immersed in oil, then no problem."

Please note the capital letters beginning the sentences and the
periods ending them.

And, I asked, "Again, why would anyone use a sealed bearing in a
system where it was immersed in oil."

Did you actually think no one would notice you contradicting yourself?!!!

Shielded bearings are often used immersed in oil if there's a possibility of
debris damaging an open bearing.

If they're double shielded, you have to rely on lubrication applied during
manufacture or use a special tool to press grease into them.

If they run in oil, all of that is irrelevant (much like you).

On 2016-06-03 09:36, wrote:
On Sunday, May 29, 2016 at 11:40:18 AM UTC-7,
wrote:
With all the bikes I have I also have a bike for which I built the
wheels on old Campy record hub on the back and DuraAce on the
front.

After getting this bike back from a friend who was saving it for me
while I was not in the best of health I rebuilt the wheels with new
balls and Campy grease.

I have mostly modern wheelsets from Campy or Fulcrum (the people
who make the modern Campy hubs etc.) These wheels have sealed
bearings. These sort of bothered me when I saw them because of the
drag of the seals. You can tell simply spinning the wheels in a
stand. But I imagined that with the weight of a person this would
be insignificant.

For the last couple of days I have been riding the old Look and in
fact you CAN feel the difference between the open bearings and the
sealed. It does coast much further and with less noise.

Has anyone else noticed this?

From the discussion it would appear that the lost of 2% of the
pedaling energy in the wheel bearings doesn't appear to be noticeable
to most people.


Which brings up a point: Suppose someone will tolerate that, which
sealed bearings are best? Requirements:

1. Industry standard, inexpensive, available everywhere.

2. Can be quickly exchanged without specialty tools.

3. The axles and hub surfaces the bearing touches aren't eaten away.

4. No finicky alignment.

5. QR not required. Actually, not even desired.


I just came back from the umpteenth cone-and-cup alignment for my MTB
and now my fingers are all oil-stained.



I most surely notice it so I assume that most of you ride well within
your limits while a large part of my time I am at or near mine. And I
am not a very fast rider anymore.


Careful. I have read in several clinical studies that spending a
substantial time at your cardiovascular limit can take a toll on your
life expectancy. Probably similar to running a car engine a hair below
redline most of the time.

I also used to go full bore for an hour or more during my rides but no
longer do that.

--
Regards, Joerg

http://www.analogconsultants.com/