Cable guide under the bottom bracket



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Lincoln Dickers

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Is there a name for the cable guide under the bottom bracket?

How often do these need replaced?

It seems like a place that could cause a considerable amount of friction but no one ever seems to
blame them when shifting gets goofy.

I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the cable
guide. Nothing looks bad but I was not sure what I should be looking for.

Thanks, Lincoln

"The bicycle is a curious vehicle: Its passenger is its engine." -John Howard
 
Just clean it off if it gets gunky. Otherwise no maintenance needed. The original guide on my
Ritchey Logic is still fine after 25K miles.

I've learned they are not absolutely necessary, even. I bought a custom Dave Yates (English builder)
and he uses a slotted bottom braket shell, the cables run right on the metal, you wouldn't know it
without looking.

Lincoln Dickerson wrote:

> Is there a name for the cable guide under the bottom bracket?
>
> How often do these need replaced?
>
> It seems like a place that could cause a considerable amount of friction but no one ever seems to
> blame them when shifting gets goofy.
>
> I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the
> cable guide. Nothing looks bad but I was not sure what I should be looking for.
>
> Thanks, Lincoln
>
> "The bicycle is a curious vehicle: Its passenger is its engine." -John Howard
 
Yow. I've seen a tube get literally rubbed through on a Cannondale Gemini just by the housing
rubbing it (granted, it was braided hydraulic housing). I know they're a lot more confined, and not
rubbing so much as pulling past, but that'd still make me a little bit uneasy.

Jon Bond

"Eddiefel" <[email protected]> wrote in message news:[email protected]...
> Just clean it off if it gets gunky. Otherwise no maintenance needed. The original guide on my
> Ritchey Logic is still fine after 25K miles.
>
> I've learned they are not absolutely necessary, even. I bought a custom Dave Yates (English
> builder) and he uses a slotted bottom braket shell, the cables run right on the metal, you
> wouldn't know it without looking.
>
>
>
> Lincoln Dickerson wrote:
>
> > Is there a name for the cable guide under the bottom bracket?
> >
> > How often do these need replaced?
> >
> > It seems like a place that could cause a considerable amount of friction but no one ever seems
> > to blame them when shifting gets goofy.
> >
> > I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the
> > cable guide. Nothing looks bad but I was not sure what I should be looking for.
> >
> > Thanks, Lincoln
> >
> > "The bicycle is a curious vehicle: Its passenger is its engine." -John Howard
>
 
This is a steel bike, not sure what the wall thickness of the shell is, but I don't expect the
cables to ever seriously cut the metal. After 4K miles the cables haven't gotten through the paint
yet. I've come to learn that this style once was not uncommon for steel bikes. It is necessary in
the case of my Yates as he uses a relieved shell (read, open hole facing the ground) for drainage.

I would think a plastic guide would be easier to cut and I've yet to see a derailleur cable make
much of a cut into one -- then again I'm only to the 25K or so on my oldest bike.

Jon Bond wrote:

> Yow. I've seen a tube get literally rubbed through on a Cannondale Gemini just by the housing
> rubbing it (granted, it was braided hydraulic housing). I know they're a lot more confined, and
> not rubbing so much as pulling past, but that'd still make me a little bit uneasy.
>
> Jon Bond
>
> "Eddiefel" <[email protected]> wrote in message news:[email protected]...
>
>>Just clean it off if it gets gunky. Otherwise no maintenance needed. The original guide on my
>>Ritchey Logic is still fine after 25K miles.
>>
>>I've learned they are not absolutely necessary, even. I bought a custom Dave Yates (English
>>builder) and he uses a slotted bottom braket shell, the cables run right on the metal, you
>>wouldn't know it without looking.
>>
>>
>>
>>Lincoln Dickerson wrote:
>>
>>
>>>Is there a name for the cable guide under the bottom bracket?
>>>
>>>How often do these need replaced?
>>>
>>>It seems like a place that could cause a considerable amount of friction but no one ever seems to
>>>blame them when shifting gets goofy.
>>>
>>>I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the
>>>cable guide. Nothing looks bad but I was not sure what I should be looking for.
>>>
>>>Thanks, Lincoln
>>>
>>>"The bicycle is a curious vehicle: Its passenger is its engine." -John Howard
>>>
>>>
>>
 
Lincoln Dickerson wrote:
> I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the
> cable guide. Nothing looks bad but I was not sure what I should be looking for.

Over time the cables will wear grooves in the guide. If the grooves get deep enough, the friction of
the cables passing through the guide will increase. This takes a long time to happen, however, and I
don't think you need to worry about this at only 6000 miles.

--
Jerry Gardner [email protected]
 
I've always called it an "under the bottom bracket cable guide". Ain't confused a bike shop with
that name yet.

May you have the wind at your back. And a really low gear for the hills! Chris

Chris'Z Corner "The Website for the Common Bicyclist": http://www.geocities.com/czcorner
 
"Lincoln Dickerson" <[email protected]> wrote in message
news:[email protected]...
> Is there a name for the cable guide under the bottom bracket?
>
> How often do these need replaced?
>
> It seems like a place that could cause a considerable amount of friction but no one ever seems to
> blame them when shifting gets goofy.
>
> I am doing an overhaul on my Bianchi Eros, about 6000 miles on it. I cleaned and inspected the
> cable guide. Nothing looks bad but I was not sure what I should be looking for.

A drop of oil on the cable guide cures some shifting problems. That's all I've ever found
necessary for them.

--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
 
Eddiefel <[email protected]> wrote in message news:<[email protected]>...

> This is a steel bike, not sure what the wall thickness of the shell is, but I don't expect the
> cables to ever seriously cut the metal. After 4K miles the cables haven't gotten through the paint
> yet. I've come to learn that this style once was not uncommon for steel bikes. It is necessary in
> the case of my Yates as he uses a relieved shell (read, open hole facing the ground) for drainage.

I had a Norco steel touring bike (Tange Infinity) and the cables cut deeply into the bb shell.

I tried the Teflon(tm) coated Slick(tm) cables, then the regular Slick(tm) cables. These are
smoother and slightly smaller diameter than the regular (cheaper) cables, so perhaps the
different diameter contributed to the rapid wear.

The bike was stolen out of my car :-(, so I don't know if the rate-of-wear slowed down once a
new, narrower groove had been worn into the bb shell.

(the cables also tended to fray and break at the bb :-( )

IMO Plastic guides, or even a section of plastic-lined cable housing, will save some grief.

hth
 
Hopefully as soon as the thief began riding the bike, the cables began working like laser beams and
cut the bike in half on a steep descent ;-)

>I had a Norco steel touring bike (Tange Infinity) and
the cables cut deeply into the bb shell. The bike was stolen out of my car
:-(, so I don't know if the rate-of-wear slowed down once a new, narrower
groove had been worn into the bb shell.
 
On Fri, 23 May 2003 16:45:53 +0000, Eddiefel wrote:

> This is a steel bike, not sure what the wall thickness of the shell is, but I don't expect the
> cables to ever seriously cut the metal. After 4K miles the cables haven't gotten through the paint
> yet. I've come to learn that this style once was not uncommon for steel bikes. It is necessary in
> the case of my Yates as he uses a relieved shell (read, open hole facing the ground) for drainage.
>
> I would think a plastic guide would be easier to cut and I've yet to see a derailleur cable make
> much of a cut into one -- then again I'm only to the 25K or so on my oldest bike.

My first road bike (Frejus) had brazed-on steel guides that routed the cables above the shell. They
never wore out, but certainly the paint did, and it would be a source of both friction and rust.

I have a plastic guide on my road bike now, which seems a good idea. Less friction, less fraying
of the cables. I just got a 10-year-old Schwinn tandem frame, which just has little guide rings on
the shells. I guess it would work OK, but again the paint will clearly wear away. It certainly
would be a point where you would have to worry about cleaning and lubrication. A nylon guide would
be less trouble.

--

David L. Johnson

__o | A foolish consistency is the hobgoblin of little minds, adored _`\(,_ | by little statesmen
and philosophers and divines. --Ralph Waldo (_)/ (_) | Emerson
 
On 23 May 2003 10:56:48 -0700, [email protected] (Lincoln Dickerson) wrote:

>It seems like a place that could cause a considerable amount of friction but no one ever seems to
>blame them when shifting gets goofy.

I've had problems here when riding with an "energy drink" in my water bottles. Any spillage
eventually finds its way to the cable guide where it can gum things up, especially in winter. When
this first happened causing upshifts to become balky it took a while to identify. A flush from a
water bottle (containing only water) cured the problem.

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3
 
"David L. Johnson" <[email protected]> wrote in message
> I just got a 10-year-old Schwinn tandem frame, which just has little guide rings > on the shells.
> I guess it would work OK, but again the paint will clearly wear away. It certainly would be a
> point where you would have to worry about cleaning and lubrication. A nylon guide would be less
> trouble.

I have a Schwinn Paramount PDG with these little guide rings. The cables are starting to wear a
groove in the BB shell. I also notice that I have to pull the cables, clean, lube, and replace about
every 3 months, when the shifting gets balky. On my other bikes with nylon guides, shifting has
never become bad enough to necessitate cleaning (though I clean every 6 months or so anyway). Maybe
I should file the rings down and glue on a nylon guide..
 
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