Re: New question, really.

Alex said:

Not too long ago Shimano offered their hubs with a 'silent clutch'
mechanism. You may have one of those hubs. Another possibility
is that a prior owner may have added grease to the hub and that
will make the hub very quiet.
----------------
Alex

No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

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

Quoted message said:

Alex said:

Not too long ago Shimano offered their hubs with a 'silent clutch'
mechanism. You may have one of those hubs. Another possibility
is that a prior owner may have added grease to the hub and that
will make the hub very quiet.
----------------
Alex

No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

--
Colin N.

Lincolnshire is mostly flat ... But the wind is mostly in your face

Colin Nelson said:

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

Quoted message said:

Alex said:

Not too long ago Shimano offered their hubs with a 'silent clutch'
mechanism. You may have one of those hubs. Another possibility
is that a prior owner may have added grease to the hub and that
will make the hub very quiet.
----------------
Alex

No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

You nailed it even before I could find the Sheldon Brown bible I
downloaded. That has to be what I have on one and only one wheel, but it
sure beats that clicking of a regular ratchet clutch.
Bill Baka

Colin Nelson said:

"Bill" <[email hidden]> wrote

Quoted message said:

Alex said:

Not too long ago Shimano offered their hubs with a 'silent clutch'
mechanism. You may have one of those hubs. Another possibility
is that a prior owner may have added grease to the hub and that
will make the hub very quiet.
----------------
Alex

No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

Sheldon's description makes it sound as though the roller clutch is the
superior design. Is there some drawback to them, perhaps faster wear or
higher manufacturing cost? I have no experience with them, but I like
the silence of the mechanism.

Ted

--
Ted Bennett

Ted Bennett said:

Colin Nelson said:

"Bill" <[email hidden]> wrote

Quoted message said:

Alex wrote:
> Not too long ago Shimano offered their hubs with a 'silent clutch'
> mechanism. You may have one of those hubs. Another possibility
> is that a prior owner may have added grease to the hub and that
> will make the hub very quiet.
> ----------------
> Alex
>
No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

Sheldon's description makes it sound as though the roller clutch is the
superior design. Is there some drawback to them, perhaps faster wear or
higher manufacturing cost? I have no experience with them, but I like
the silence of the mechanism.

Ted

They are pretty unbreakable by a human rider under 300 pounds. I have
one in my 1966 Chrysler 440 and it takes well over 1,000 foot pounds of
torque when I nail it. It is probably one of the strongest one way
clutch designs ever made. Since they are used in car automatics they
have to be quiet or the cars wouldn't sell.
Bill Baka

Ted Bennett said:

Colin Nelson said:

"Bill" <[email hidden]> wrote

Quoted message said:

Alex wrote:
> Not too long ago Shimano offered their hubs with a 'silent clutch'
> mechanism. You may have one of those hubs. Another possibility
> is that a prior owner may have added grease to the hub and that
> will make the hub very quiet.
> ----------------
> Alex
>
No extra grease as far as I can tell. This must be a 'silent clutch'
because there is absolutely zero noise when coasting. I have to think
that it is similar to an automatic cars' sprague clutch where the roller
bearings are loose in one direction but bind up in the other. This is
used in Ford and Chrysler (older) transmissions for a non-binding 1-2
shift. For low gear downhill there is a band. Shimano may indeed have
used this so I will attempt to poke around there, or maybe the Sheldon
Brown stuff has a reference.
Now somewhere in 300 GB I know I have it.
Thanks,
Bill Baka

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

Sheldon's description makes it sound as though the roller clutch is the
superior design. Is there some drawback to them, perhaps faster wear or
higher manufacturing cost? I have no experience with them, but I like
the silence of the mechanism.

Ted

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

Shimano silent clutch freehubs will function at 60 below with no special
treatment. Instead of pawls, they drive through about two dozen eighth
inch cylinders that roll into pockets and jam to drive, backing out a
little to coast.

They’re called RO-80 and cost and look about the same as LX. They engage
with less pedal motion at warm temperatures than pawl freehubs and take
a little longer to engage at lower temperatures. While they always work
at low temperatures, winterization brings them back to near-instant
engagement no matter how cold it gets. They’re pretty much cold proof
since they depend on the viscosity of the grease to move the rollers
into engagement. They’re about 120 grams heavier than LX.
*************************************************************

Ted Bennett said:

Quoted message said:

Quoted message said:

> Not too long ago Shimano offered their hubs with a 'silent
> clutch' mechanism. You may have one of those hubs. Another
> possibility is that a prior owner may have added grease to the
> hub and that will make the hub very quiet.

Quoted message said:

Quoted message said:

Quoted message said:

No extra grease as far as I can tell. This must be a 'silent
clutch' because there is absolutely zero noise when coasting. I
have to think that it is similar to an automatic cars' sprague
clutch where the roller bearings are loose in one direction but
bind up in the other. This is used in Ford and Chrysler (older)
transmissions for a non-binding 1-2 shift. For low gear downhill
there is a band. Shimano may indeed have used this so I will
attempt to poke around there, or maybe the Sheldon Brown stuff has
a reference. Now somewhere in 300 GB I know I have it.

Quoted message said:

Quoted message said:

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

Quoted message said:

Sheldon's description makes it sound as though the roller clutch is
the superior design. Is there some drawback to them, perhaps faster
wear or higher manufacturing cost? I have no experience with them,
but I like the silence of the mechanism.

They are widely used in automatic transmissions and last a long time
with insignificant wear. As I mentioned, their problem in bicycle use
is that there is no space for them in reliable dimensions.

Jobst Brandt

Quoted message said:

Ted Bennett said:

Quoted message said:

>> Not too long ago Shimano offered their hubs with a 'silent
>> clutch' mechanism. You may have one of those hubs. Another
>> possibility is that a prior owner may have added grease to the
>> hub and that will make the hub very quiet.

Quoted message said:

Quoted message said:

> No extra grease as far as I can tell. This must be a 'silent
> clutch' because there is absolutely zero noise when coasting. I
> have to think that it is similar to an automatic cars' sprague
> clutch where the roller bearings are loose in one direction but
> bind up in the other. This is used in Ford and Chrysler (older)
> transmissions for a non-binding 1-2 shift. For low gear downhill
> there is a band. Shimano may indeed have used this so I will
> attempt to poke around there, or maybe the Sheldon Brown stuff has
> a reference. Now somewhere in 300 GB I know I have it.

Quoted message said:

Quoted message said:

Right here :- http://sheldonbrown.com/gloss_ri-z.html#rollerclutch

Quoted message said:

Sheldon's description makes it sound as though the roller clutch is
the superior design. Is there some drawback to them, perhaps faster
wear or higher manufacturing cost? I have no experience with them,
but I like the silence of the mechanism.

They are widely used in automatic transmissions and last a long time
with insignificant wear. As I mentioned, their problem in bicycle use
is that there is no space for them in reliable dimensions.

Jobst Brandt

I did post that they were similar to car transmissions but as you have
noted, the force vectors are much different. A car uses everything in a
straight line (inside the transmission) so there is no force other than
1 single rotational torque.
Bill Baka