Sealed Bearings

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?

On 2016-05-29 11:40, 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?


No, but was that with the very same tires and tire pressures front and back?

A friend of mine has an old Peugeot which still needs to be restored.
Decades ago he equipped that with Phil Woods seal bearings front and
back and those wheels spin just as freely as on my Shimano 600 set. The
wheels on my MTB do spin less freely but that's because each side has
double rubbers to keep out dirt (more or less).

--
Regards, Joerg

http://www.analogconsultants.com/

On 30/05/16 04:40, 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?


You must be very sensitive, or the sealed units you have are extremely
high friction compared with what's normal. IIRC, each seal contributes
about 0.5W at 50km/h.

--
JS

trade grease for: http://www.amazon.com/s/ref=nb_sb_no...ial%2Cmodifier

in drops.

or repack a freehub then repack a freewheel. freewheels win.

if you're good a this then grade 25 balls in new cones, straight axle, roll better than inexpensive dull Chinese balls.

you would add in all the friction savers but Muzi's build will be %15 faster

seals have an edge once broken in that rides on a layer of rotationally extruded/thrown off lubricant.

I guess grease piles up on seals ID for more friction but....a better seal whereas slimey synthetics would flow under.

that is in facto what muh Ford 5.4 SOHC does with recommended 5-20 synthetic (Valvo).The thinness lubes rings but burns off clean into the convertor (ruining it) Does not burn oil running steady but stop n go draws oil past rings for lubrication.

trade for cartridge bearings

On 5/29/2016 2:40 PM, 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?

FWIW, of my four most-ridden bikes, two have sealed bearing hubs and two
do not. I can't tell the difference in the hubs. Perhaps it's because
the bikes are quite different; but even on the workstand, I haven't
noticed any difference.

--
- Frank Krygowski

On 2016-05-29 20:03, Frank Krygowski wrote:
On 5/29/2016 2:40 PM, 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?

FWIW, of my four most-ridden bikes, two have sealed bearing hubs and two
do not. I can't tell the difference in the hubs. Perhaps it's because
the bikes are quite different; but even on the workstand, I haven't
noticed any difference.


No wonder. Just imagine what would happen if only 2% of a sporty rider's
200W would be lost in the bearings. That would come to 1W dissipation
per bearing and they'd become very toasty. Yet they never do.

--
Regards, Joerg

http://www.analogconsultants.com/

On 2016-06-01 17:55, Phil W Lee wrote:
Joerg considered Wed, 01 Jun 2016
10:02:11 -0700 the perfect time to write:

On 2016-05-29 20:03, Frank Krygowski wrote:
On 5/29/2016 2:40 PM, 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?

FWIW, of my four most-ridden bikes, two have sealed bearing hubs and two
do not. I can't tell the difference in the hubs. Perhaps it's because
the bikes are quite different; but even on the workstand, I haven't
noticed any difference.


No wonder. Just imagine what would happen if only 2% of a sporty rider's
200W would be lost in the bearings. That would come to 1W dissipation
per bearing and they'd become very toasty. Yet they never do.

I think you'll find that a typical aluminium bicycle wheel hub will
VERY easily dissipate quite a few watts - probably well into double
digits - without getting in the least bit toasty, with only the normal
airflow to cool it.


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.


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.

--
Regards, Joerg

http://www.analogconsultants.com/

On 6/2/2016 12:40 PM, Joerg wrote:
On 2016-06-01 17:55, Phil W Lee wrote:
Joerg considered Wed, 01 Jun
2016
10:02:11 -0700 the perfect time to write:

On 2016-05-29 20:03, Frank Krygowski wrote:
On 5/29/2016 2:40 PM, 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?

FWIW, of my four most-ridden bikes, two have sealed
bearing hubs and two
do not. I can't tell the difference in the hubs.
Perhaps it's because
the bikes are quite different; but even on the
workstand, I haven't
noticed any difference.


No wonder. Just imagine what would happen if only 2% of a
sporty rider's
200W would be lost in the bearings. That would come to 1W
dissipation
per bearing and they'd become very toasty. Yet they never
do.

I think you'll find that a typical aluminium bicycle wheel
hub will
VERY easily dissipate quite a few watts - probably well
into double
digits - without getting in the least bit toasty, with
only the normal
airflow to cool it.


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.


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.



There's nothing new in bearing seals, big selection:

http://www.skf.com/au/products/beari...als/index.html


The seal type is the last part of the bearing number. If you
need tighter sealing or more free running seals, buy a
bearing with a different suffix.

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

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!

--
JS

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 :-)
--
cheers,

John B.