Freehub does not engage in cold

On Jan 26, 12:38 pm, "Sir Ridesalot" <[email hidden]>

Quoted message said:

Hello oh helpful ones.

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

I visited with the people for about an hour and then went to ride home.
No joy!

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions. I ended
up walking home. I was very happy this did not happen in the boonies
where I often ride.

The freehub had not gotten any snow or water on it. After it was inside
for a short period of time it worked fine.

Therefore I think it might be some kind of condensation issue.

Shimano

Why was I able to ride the four blocks when I first took the bike out?

Why did the freehub not engage? Condensation in the freehub froze while
sitting?

Is there any way I could have got the freehub to engage again while it
was outside?

What can I do to prevent this from happening again?

Thanks for all relevant answers.

Peter

Hi there.

Sorry. I meant to mention the hub is a seven gear Shimano Alivio.

Peter

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in the
largest sprocket. There also seems to be a correlation between failure
of metal components and the cold; on one unusually freezing ride I lost
a spoke and another rider snapped a crank.

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in the
largest sprocket. There also seems to be a correlation between failure
of metal components and the cold; on one unusually freezing ride I lost
a spoke and another rider snapped a crank.

Dear Zog,

Yes, two-wheeled objects break more easily when it's cold:

http://groups.google.com/group/rec.bicycles.tech/msg/df3cb7fe3a3eb450

Cheers,

Carl Fogel

Sir Ridesalot said:

Hello oh helpful ones.

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

I visited with the people for about an hour and then went to ride
home. No joy!

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions.

{snip}

Quoted message said:

What can I do to prevent this from happening again?

Stop delivering kitchen chairs via mountain bike.

Quoted message said:

Thanks for all relevant answers.

Don't mention it.

<eg>

On Jan 26, 12:45 pm, "Sir Ridesalot" <[email hidden]>

Quoted message said:

On Jan 26, 12:38 pm, "Sir Ridesalot" <[email hidden]>

Quoted message said:

Hello oh helpful ones.

Quoted message said:

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

Quoted message said:

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

Quoted message said:

I visited with the people for about an hour and then went to ride home.
No joy!

Quoted message said:

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions. I ended
up walking home. I was very happy this did not happen in the boonies
where I often ride.

Quoted message said:

The freehub had not gotten any snow or water on it. After it was inside
for a short period of time it worked fine.

Quoted message said:

Therefore I think it might be some kind of condensation issue.

Quoted message said:

Shimano

Quoted message said:

Why was I able to ride the four blocks when I first took the bike out?

Quoted message said:

Why did the freehub not engage? Condensation in the freehub froze while
sitting?

Quoted message said:

Is there any way I could have got the freehub to engage again while it
was outside?

Quoted message said:

What can I do to prevent this from happening again?

This used to happen to me on occasion, and the only solution was to
bring it indoors for a few minutes. Of course, that's not always an
option when you're visiting someone's home or office! I got tired of
that (and slushy, gummed up derailers) and my winter bike now sports a
Shimano Nexus 7. Love it!

http://drumbent.com/winterbike.html

Mark

In article <45ba4ced.0@entanet>,

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in
the largest sprocket. There also seems to be a correlation between
failure of metal components and the cold; on one unusually freezing
ride I lost a spoke and another rider snapped a crank.

For metals, the variations in temperatures that humans can survive in
tend to be not very significant. Perhaps you've had a spoke break at
70F as well? It takes temperatures much colder than this to cause most
metals to get brittle. Were that not the case, we couldn't very easily
send rockets, ships and satellites into space.

Water getting into the mechanism and freezing can be an issue, but
usually not for freewheels which have some degree of sealing. Oils
thicken somewhat at -20C, but as I understand it the culprit in greases
thickening in the cold is the soap emulsion.

Tim McNamara said:

In article <45ba4ced.0@entanet>,

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in
the largest sprocket. There also seems to be a correlation between
failure of metal components and the cold; on one unusually freezing
ride I lost a spoke and another rider snapped a crank.

For metals, the variations in temperatures that humans can survive in
tend to be not very significant. Perhaps you've had a spoke break at
70F as well? It takes temperatures much colder than this to cause most
metals to get brittle. Were that not the case, we couldn't very easily
send rockets, ships and satellites into space.

[snip]

Dear Tim,

Actually, the temperatures mentioned can affect steel severely.

For example, -18C to -29C (-0F to -20F) can contribute to bridges
collapsing:

"The quality of the steel used for the hanger rods also played a role
in the failure. Metallurgical tests performed on the hanger rods (See
Appendix B*) indicate that the steel that was used did not remain
ductile in temperatures below –18 degrees Celsius, since the ductile
to brittle transition temperature was between –18 and –29 degrees
Celsius. Although the cold temperature contributed to the failure of
Hanger 3 (NW) and the partial collapse of the deck on January 14,
2003, it was not the ultimate cause of failure. The hanger would have
failed eventually due to fatigue and microscopic brittle cracking that
occurred gradually over a period of several years. However, as noted
by the metallurgist (Appendix B), the brittleness of the steel in cold
temperatures accelerated the microscopic brittle cracking over the
years in addition to the onset of final fracture."

http://www.mto.gov.on.ca/english/engineering/cosens/

The transition temperature from ductile to brittle can vary
considerably, according to the alloy, but metal failure in colder
climates is a well-known problem.

Cheers,

Carl Fogel

Sir Ridesalot said:

What can I do to prevent this from happening again?

1) do not take the bike indoors but keep it cold
2) winterize the freehub (see icebike)
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

On Jan 26, 9:38 am, "Sir Ridesalot" <[email hidden]>

Quoted message said:

Hello oh helpful ones.

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

I visited with the people for about an hour and then went to ride home.
No joy!

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions. I ended
up walking home. I was very happy this did not happen in the boonies
where I often ride.

The freehub had not gotten any snow or water on it. After it was inside
for a short period of time it worked fine.

Therefore I think it might be some kind of condensation issue.

Shimano

Why was I able to ride the four blocks when I first took the bike out?

Why did the freehub not engage? Condensation in the freehub froze while
sitting?

Is there any way I could have got the freehub to engage again while it
was outside?

What can I do to prevent this from happening again?

Thanks for all relevant answers.

Peter

Either water or grease that got really sticky at -4 degrees. Flush well
and then oil with Mobil One..First couple of times you coasted, making
the pawls go down, they just stayed down, not engaging the teeth when
you pedaled.

On Jan 26, 5:47 pm, "Qui si parla Campagnolo" <[email hidden]>

Quoted message said:

On Jan 26, 9:38 am, "Sir Ridesalot" <[email hidden]>

Quoted message said:

Hello oh helpful ones.

Quoted message said:

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

Quoted message said:

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

Quoted message said:

I visited with the people for about an hour and then went to ride home.
No joy!

Quoted message said:

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions. I ended
up walking home. I was very happy this did not happen in the boonies
where I often ride.

Quoted message said:

The freehub had not gotten any snow or water on it. After it was inside
for a short period of time it worked fine.

Quoted message said:

Therefore I think it might be some kind of condensation issue.

Quoted message said:

Shimano

Quoted message said:

Why was I able to ride the four blocks when I first took the bike out?

Quoted message said:

Why did the freehub not engage? Condensation in the freehub froze while
sitting?

Quoted message said:

Is there any way I could have got the freehub to engage again while it
was outside?

Quoted message said:

What can I do to prevent this from happening again?

Quoted message said:

Thanks for all relevant answers.

Quoted message said:

PeterEither water or grease that got really sticky at -4 degrees. Flush well

and then oil with Mobil One..First couple of times you coasted, making
the pawls go down, they just stayed down, not engaging the teeth when
you pedaled.- Hide quoted text -- Show quoted text -

Hi and thanks to those of you who replied to the topic. :<😉

My mountain bike is my primary winter transportation. I *NEED* it to be
*DEPENDABLE*!

If this had happened when I was on my commute where there is no public
transportation I could have been in very serious trouble facing a 15
mile walk home.

I had pedaled and coasted on the way out. When I came out of the house
to return home the freehub simply spun. No clicking of the ratchets at
all. That happened as positioned the pedal for the downstroke as I
tried to start pedalling.

Leaving the bike outside here is *NOT* an option if I want to see it in
the morning or have all the parts stay on it.

Some one said to winterize the free hub see icebike but did not provide
either a link or instructions. How do you winterize a freehub?

Thank goodness I had my Miele road boke with cyclo-cross tyres on it to
fall back on for transportation today.

It is still snowing here and I fear that the snow will be too deep for
the Miele tomorrow. I also do not want the hub to free spin again.

What should I flush the hub with?

What is the best method to use to flush it?

Thanks very much for your interest.

Peter

"Sir Ridesalot" <[email hidden]> a écrit:

Quoted message said:

Some one said to winterize the free hub see icebike but did not
provide either a link or instructions. How do you winterize a freehub?

Googling [winterize icebike] or [winterize freehub] gives:

http://www.icebike.org/Equipment/freehub.htm

Quoted message said:

If this had happened when I was on my commute where there
is no public transportation I could have been in very serious
trouble facing a 15 mile walk home.

I've read that urinating on a freehub body will temporarily free frozen
pawls.

James Thomson

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in the
largest sprocket. There also seems to be a correlation between failure
of metal components and the cold; on one unusually freezing ride I lost
a spoke and another rider snapped a crank.

If you're like me, you may just be better remembering the breakdowns that
happen on very cold days because it's such a pita to make repairs --
taking off your gloves, handling metal tools, etc.

On Fri, 26 Jan 2007 19:13:36 -0600, Gary Young <[email hidden]>

Quoted message said:

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in the
largest sprocket. There also seems to be a correlation between failure
of metal components and the cold; on one unusually freezing ride I lost
a spoke and another rider snapped a crank.

If you're like me, you may just be better remembering the breakdowns that
happen on very cold days because it's such a pita to make repairs --
taking off your gloves, handling metal tools, etc.

Dear Gary,

Low-carbon steel has ductile to brittle problems in such temperatures:

http://www.key-to-steel.com/Articles/Art136.htm

Cheers,

Carl Fogel

-snip-

Quoted message said:

I've read that urinating on a freehub body will temporarily free frozen
pawls.

James Thomson

Sounds like the 'ol urban ledged of pissing on body parts to unfreeze
them from metal.

Seriously, I would try a Freehub Buddy & Moringstar seal, w/ a through
flushing w/ a non-freezable solvent & Mag 1 or some such, prior to a
full assembly. If the Freehub Buddy approach didn't do the job then go
to the full disassembly method.

John

Sir Ridesalot said:

Last night at nine PM I took my mountain bike out to deliver three
kitchen chairs four blocks away.

The temperature was -20 C (-4 F) and I left the bicycle on an
unenclosed porch while I visited.

I visited with the people for about an hour and then went to ride home.
No joy!

The freehub spun uselessly. It (pawls) would not engage. It did not
matter what I did the freehub spun freely in both directions. I ended
up walking home. I was very happy this did not happen in the boonies
where I often ride.

The freehub had not gotten any snow or water on it. After it was inside
for a short period of time it worked fine.

Therefore I think it might be some kind of condensation issue.

I've seen this happen with freewheels when the grease gets so thick that
the ratchet pawls can't drop down to engage the teeth. The fix is to
clean out all the grease and use a light oil in the winter.

--

John ([email hidden])

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Tim McNamara said:

In article <45ba4ced.0@entanet>,

Zog The Undeniable said:

Tim McNamara wrote:
> The grease in the pawls thickened up in the cold. Freehubs and
> freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in
the largest sprocket. There also seems to be a correlation between
failure of metal components and the cold; on one unusually freezing
ride I lost a spoke and another rider snapped a crank.

For metals, the variations in temperatures that humans can survive in
tend to be not very significant. Perhaps you've had a spoke break at
70F as well? It takes temperatures much colder than this to cause most
metals to get brittle. Were that not the case, we couldn't very easily
send rockets, ships and satellites into space.

[snip]

Dear Tim,

Actually, the temperatures mentioned can affect steel severely.

For example, -18C to -29C (-0F to -20F) can contribute to bridges
collapsing:

"The quality of the steel used for the hanger rods also played a role
in the failure. Metallurgical tests performed on the hanger rods (See
Appendix B*) indicate that the steel that was used did not remain
ductile in temperatures below -18 degrees Celsius, since the ductile
to brittle transition temperature was between -18 and -29 degrees
Celsius. Although the cold temperature contributed to the failure of
Hanger 3 (NW) and the partial collapse of the deck on January 14,
2003, it was not the ultimate cause of failure. The hanger would have
failed eventually due to fatigue and microscopic brittle cracking that
occurred gradually over a period of several years. However, as noted
by the metallurgist (Appendix B), the brittleness of the steel in cold
temperatures accelerated the microscopic brittle cracking over the
years in addition to the onset of final fracture."

http://www.mto.gov.on.ca/english/engineering/cosens/

The transition temperature from ductile to brittle can vary
considerably, according to the alloy, but metal failure in colder
climates is a well-known problem.

Cheers,

Carl Fogel

Ships too. In 1947 the USS Ponaganset broke in two while tied up at a dock
in Boston harbor. The Temperature was 35° F (1.66° C).

This website suggests the Titanic sank from low temperature brittle
fracture. At the bottom of the page there's documentation on the sinking
of the USS Ponaganset.

Chas.

"Gary Young" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Zog The Undeniable said:

Tim McNamara said:

The grease in the pawls thickened up in the cold. Freehubs and
freewheels should be lubed with oil, not grease.

I think -20 Centigrade would trouble a lot of oils too! I remember
doing a paper round when it was about -10 deg C in the UK; water got
into the gear cable outer and froze, meaning the bike was stuck in the
largest sprocket. There also seems to be a correlation between

failure

Quoted message said:

Quoted message said:

of metal components and the cold; on one unusually freezing ride I

lost

Quoted message said:

Quoted message said:

a spoke and another rider snapped a crank.

If you're like me, you may just be better remembering the breakdowns

that

Quoted message said:

happen on very cold days because it's such a pita to make repairs --
taking off your gloves, handling metal tools, etc.

That was the motivation for Tuillio Campagnolo to design his quick release
system to replace wing nuts on wheels. In 1924 during a race he ran into a
snow storm on the Croce d'Aune pass near Padova, Italy. He wasn't using a
derailleur just a double sided hub with different sized sprockets. His
fingers were too cold to loosen the wing nuts on his rear wheel to flip
the wheel around to use the larger sprocket for climbing. He ended up
using the small sprocket to finish the climb.

Chas.

* * Chas said:

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Tim McNamara said:

In article <45ba4ced.0@entanet>,
Zog The Undeniable <[email hidden]> wrote:

> Tim McNamara wrote:
> > The grease in the pawls thickened up in the cold. Freehubs and
> > freewheels should be lubed with oil, not grease.
>
> I think -20 Centigrade would trouble a lot of oils too! I remember
> doing a paper round when it was about -10 deg C in the UK; water got
> into the gear cable outer and froze, meaning the bike was stuck in
> the largest sprocket. There also seems to be a correlation between
> failure of metal components and the cold; on one unusually freezing
> ride I lost a spoke and another rider snapped a crank.

For metals, the variations in temperatures that humans can survive in
tend to be not very significant. Perhaps you've had a spoke break at
70F as well? It takes temperatures much colder than this to cause most
metals to get brittle. Were that not the case, we couldn't very easily
send rockets, ships and satellites into space.

[snip]

Dear Tim,

Actually, the temperatures mentioned can affect steel severely.

For example, -18C to -29C (-0F to -20F) can contribute to bridges
collapsing:

"The quality of the steel used for the hanger rods also played a role
in the failure. Metallurgical tests performed on the hanger rods (See
Appendix B*) indicate that the steel that was used did not remain
ductile in temperatures below -18 degrees Celsius, since the ductile
to brittle transition temperature was between -18 and -29 degrees
Celsius. Although the cold temperature contributed to the failure of
Hanger 3 (NW) and the partial collapse of the deck on January 14,
2003, it was not the ultimate cause of failure. The hanger would have
failed eventually due to fatigue and microscopic brittle cracking that
occurred gradually over a period of several years. However, as noted
by the metallurgist (Appendix B), the brittleness of the steel in cold
temperatures accelerated the microscopic brittle cracking over the
years in addition to the onset of final fracture."

http://www.mto.gov.on.ca/english/engineering/cosens/

The transition temperature from ductile to brittle can vary
considerably, according to the alloy, but metal failure in colder
climates is a well-known problem.

Cheers,

Carl Fogel

Ships too. In 1947 the USS Ponaganset broke in two while tied up at a dock
in Boston harbor. The Temperature was 35° F (1.66° C).

This website suggests the Titanic sank from low temperature brittle
fracture. At the bottom of the page there's documentation on the sinking
of the USS Ponaganset.

Chas.

Dear Chas,

Pre-1947 Liberty ships are often cited as examples of how nothing more
than cold water could embrittle steel:

"Many Liberty ships suffered hull and deck cracks, and some were lost
to such structural defects. During WWII, there were nearly 1,500
serious brittle fractures. Nineteen ships broke in half without
warning, including the SS John P. Gaines[2][3], which sank on 24
November 1943 with the loss of 10 lives. The ships were built in great
haste, often by inexperienced people, in the era before the effects of
low temperatures in embrittlement of steel were well understood.
Temperatures in the North Atlantic could be low enough for the hull
steel to fracture relatively easily."

http://en.wikipedia.org/wiki/Liberty_ships

The famous Boston molasses-tank failure is also often mentioned--I
remember reading about it, but missed the comments about how the
temperature had dropped to 2F the day before the disaster.

Here's a excerpt from a more technical page:

"The most dramatic and unexpected cause of brittle failure in ferrous
alloys is their tendency to lose almost all of their toughness when
the temperature drops below their ductile to brittle transition
temperature. This has been the cause for numerous dramatic and
catastrophic failures, i.e. the rupture of a 2.3 million gallon
molasses storage tank in the winter of 1911, bridge failures, liberty
ships breaking in half in the harbor and at sea during World War II
and other disasters (see ASTM STP 158, and the figures and text
following the references). The earliest record of such failures dates
back to 1879. This was when good, cheap Bessemer and open hearth
steels had just begun to become widely used. (The Bessemer process was
introduced in 1860. Prior to that, steel had been made by an expensive
process of carburizing wrought iron. The expense limited the uses of
steel to special applications.) The problem of brittle failure of
steel structures was severe during and just after World War II.
Between 1942 and 1952 around 250 large welded steel ships were lost
due to catastrophic brittle failure. Another 1200 welded ships
suffered relatively minor damage (cracks less than 10 feet long) while
over 1900 riveted ship have broken in two or lost at sea. Over 58
cases of non-ship failures had been reported. Many of these may have
failed by non-brittle processes while many failures probably have gone
unreported due to adverse publicity it would generate [3]."

http://www.matsci.ucdavis.edu/MatSciLT/EMS-174L/Files/DuctileBrittleTransition.pdf

Cheers,

Carl Fogel