Bicycle Mechanics - Rusted rear derailleur cable

I have a rusted rear derailleur cable. The bike is a 1987 Trek 400 but the drivetrain is a new Ultegra rear derailleur operated by an indexed Dura Ace bar-end shifter.

This is my rain/winter bike, so it will see water and road salt this time of year. I had my lbs install Jagwire a year ago. The install is pictured below. The cable runs over a guide that is below the BB, then runs into the chainstay.

http://i289.photobucket.com/albums/ll210/wildcat-bucket/Jan2010012.jpg


I would like to find the best way to install the cable, It seems to be rusted within the chainstay.

I have a rusted rear derailleur cable. The bike is a 1987 Trek 400 but the drivetrain is a new Ultegra rear derailleur operated by an indexed Dura Ace bar-end shifter.

This is my rain/winter bike, so it will see water and road salt this time of year. I had my lbs install Jagwire a year ago. The install is pictured below. The cable runs over a guide that is below the BB, then runs into the chainstay.

http://i289.photobucket.com/albums/ll210/wildcat-bucket/Jan2010012.jpg


I would like to find the best way to install the cable, It seems to be rusted within the chainstay.
I'm not sure I understand your question. Are you having difficulty extracting it, or are you looking for tricks to feed the cable through and find the hole?
I've never run a cable through a chainstay like that, but I've run internal cables through top tubes. Mind you, they had the housing running through the tube as well, so the holes were a lot larger, so I'm not sure the same tricks will work. Perhaps you could use the existing cable as a lead to draw the replacement through as long as you could couple them compactly enough to fit through the hole.
Have you considered Gore Ride on cables? They have a housing liner that covers the full length of the inner cable, covering the otherwise exposed length.

Perhaps you could use the existing cable as a lead to draw the replacement through as long as you could couple them compactly enough to fit through the hole.

I would try this, but you'll have to do it twice because if you mate them end-to-end your new cable will be going the wrong direction! There might be some sort of internal guide, but then again maybe not. I would imagine if you pull the cable out and there isn't a guide it'll be nearly impossible to replace.

Alternatively you could run solid housing along the top tube and down the seat stay. It won't look great, but it would keep the cable out of harm's way and less prone to rusting.

I would try this, but you'll have to do it twice because if you mate them end-to-end your new cable will be going the wrong direction! There might be some sort of internal guide, but then again maybe not. I would imagine if you pull the cable out and there isn't a guide it'll be nearly impossible to replace.

Alternatively you could run solid housing along the top tube and down the seat stay. It won't look great, but it would keep the cable out of harm's way and less prone to rusting.

You don't have to do it twice. You're discarding the old cable, so just cut it forward of the chainstay and pull the new one through.
Another thought I had was a vacuum cleaner. It will draw a string through a tiny hole, I wonder if it would work with a cable.

I had a very similar frame ('87 Trek 560) and feeding a new cable through the chainstay wasn't that difficult. Use a new cable with the welded end so there are no loose strands and just keep trying until it finds the exit hole. It may take a few attempts but it will work.

As noted, you may want to use teflon coated, or at least die drawn staniless steel cables to avoid future rust. Also, spraying Frame Saver into the chainstay is worthwhile to protect the interior of the tubing.

Another option I used on a particularly difficult Talon bike with internal cable routing was to use an old bit of housing as a guide. You just cut existing cable so there are just a few inches sticking out either side of the stay. Then thread a piece of housing onto the cable so there is a little housing sicking out each side of stay; pull out old cable, using the housing in the stay as the guide, thread new cable through. Once cable is all the way through , pull housing out.

Hi,

Thank you all for the recommendations.

I'll combine the SS cable suggestion and also try to shield the cable by extending the housing.

Any suggestions for a SS cable by brand name?

Michael

It doesn't make sense to me to use anything but stainless cables. My LBS doesn't use or sell anything else.

Hi,

Thank you all for the recommendations.

I'll combine the SS cable suggestion and also try to shield the cable by exstending the housing.

Any suggestions for a SS cable by brand name?

Michael

once you get into stainless cables, the quality is very good. any choice will be fine but jagwire slick stainless is good.

Another option I used on a particularly difficult Talon bike with internal cable routing was to use an old bit of housing as a guide. You just cut existing cable so there are just a few inches sticking out either side of the stay. Then thread a piece of housing onto the cable so there is a little housing sicking out each side of stay; pull out old cable, using the housing in the stay as the guide, thread new cable through. Once cable is all the way through , pull housing out.
The problem with this is that these Trek frames have holes in the stay that are too small for housing so only the inner wire goes through it.

The problem with this is that these Trek frames have holes in the stay that are too small for housing so only the inner wire goes through it.

Ah, that would be a problem

The problem with this is that these Trek frames have holes in the stay that are too small for housing so only the inner wire goes through it.

Yes, this is the real problem. The cable is binding in that last part of the housing between the RD and the chain stay.

Die drawn cables wires in cable have been flattened on the outside ,
QBP has those, in stainless steel.
smooth = less friction
You can also get a Teflon coated stainless cables.
less friction too.
same distributor, via your LBS.


It may be picking up Iron oxide from the steel frame,

as it passes under the BB ..

so maybe a Teflon tube thru that guide will help.

Die drawn cables wires in cable have been flattened on the outside ,
QBP has those, in stainless steel.
smooth = less friction
You can also get a Teflon coated stainless cables.
less friction too.
same distributor, via your LBS.


It may be picking up Iron oxide from the steel frame,

as it passes under the BB ..

so maybe a Teflon tube thru that guide will help.
That's precisely why I suggested the Gore cable sets. Great solution for this type of application.

That's precisely why I suggested the Gore cable sets. Great solution for this type of application.

I think Satan invented internal cable routing.

I think Satan invented internal cable routing.
It gets points for neatness though if done right.

I think Satan invented internal cable routing.

its not that bad. the small black liner stuff is good for threading into the old cable to use as a guide. fits better than housing. a good magnet or pickup tool helps too. a twist and poke/prod of the inner wire will get the cable unjammed and right out the hole if you don't have the "cheater liner".

Hi Dan,

Would I attemp to install the Gore cable & housing internally within the chainstay? Or do you suggest that I just zip-tie a full length cable & housing along the frame?

I'll consider either, this is just my winter & rain bike.

Michael

One suggestion is to take a sharpened old spoke and try reaming out the holes from both ends of the chainstay. Your problems getting the cable through it might be from rust or dirt accumulation inside and the spoke could loosen and push it aside. Perhaps a compressed air blast would clean it out afterward.

These internal stay routed cables are a PIA if the stay gets crudded up inside but work ok if it's clean.

Hi Dan,

Would I attemp to install the Gore cable & housing internally within the chainstay? Or do you suggest that I just zip-tie a full length cable & housing along the frame?

I'll consider either, this is just my winter & rain bike.

Michael
To install these, you first cut and fit the outer housings between the stops, then insert the liner, which runs the full length of the cable, even between the housing stops. The last step is to insert the cable.
The cables are slicker even than teflon in my opinion. I don't have them on any of my bikes, but I've installed them for others.
I use full length housing on most of mine,(only because they are gearhubs) but if that bike was mine, I don't think I'd do that except as a last resort.

For a winter / rain bike a continuous housing makes a lot of sense as this protects the cable from the elements and removes points of access for water.

For an indexed system high quality cables and housings and smooth cable routing is key.

My mountain bike sees a lot of water and sticky dirt and I have continuous runs of housing to keep things clean... I run a 9 speed indexed system and it works flawlessly no matter how dirty things get.

To install these, you first cut and fit the outer housings between the stops, then insert the liner, which runs the full length of the cable, even between the housing stops. The last step is to insert the cable.
The cables are slicker even than teflon in my opinion. I don't have them on any of my bikes, but I've installed them for others.
I use full length housing on most of mine,(only because they are gearhubs) but if that bike was mine, I don't think I'd do that except as a last resort.

Hi Dan,

I watched this video from Gore: http://www.rideoncables.com/en_us/support/support_slfsder.html

The last question I have about this system is fitting the liner on the guide under the BB. Do I just run the liner over the guide, or do I trim the liner and install the cable directly to the guide?

Michael

Hi Dan,

I watched this video from Gore: http://www.rideoncables.com/en_us/support/support_slfsder.html

The last question I have about this system is fitting the liner on the guide under the BB. Do I just run the liner over the guide, or do I trim the liner and install the cable directly to the guide?

Michael
That's a good question, and I don't really know the answer. I don't think I've done an under the bb install on these. I think to get the benefit of the system requires using the liner full length though, so I'm sure that's the way it's supposed to be done.
I'd not seen that video before, thanks for the link.
BTW, happy new year.

For a winter / rain bike a continuous housing makes a lot of sense as this protects the cable from the elements and removes points of access for water.

For an indexed system high quality cables and housings and smooth cable routing is key.

My mountain bike sees a lot of water and sticky dirt and I have continuous runs of housing to keep things clean... I run a 9 speed indexed system and it works flawlessly no matter how dirty things get.

Hi 65er,

I'd be happy to consider the full length cable housing strategy. The bike has a full length housing for the rear brake now.

Would I just zip tie the new cable-within-a-housing to the frame? Would I need a special attachment point to the rear drop-out area for the housing and/or cable to achieve a reliable installation?

Michael

If you want to go full length with the housing, its best to secure the housing to the chainstay with a cable clip so the loop to the derailleur stays consistant. It's also much neater. Sturmey Archer makes casing guide clips in several sizes starting at about 15 mm up to 28.6mm. Zip ties work, but the casing clips are neater.

My suggestion for routing the new cable through the stay is to slide a piece of housing liner down the existing cable, then pull the old cable out and leave the liner in place. Slide the new cable into the liner and remove the liner (or better still - trim it so that an inch or so protrudes at each end, and leave it in place.)

Hopefully the cable isn't too rusted to get the liner in over it...

Hopefully the cable isn't too rusted to get the liner in over it...

The existing cable is the Shimano item that came with my Dura Ace ten speed indexed bar-end shifters.

I'm assuming that this is not stainless steel. Is that correct?

Stainless alloys are rust resistant, but not rustproof, though it does take a pretty corrosive environment to cause significant rust.

You can test the cable with a magnet, stainless steel is non-magnetic.

You can test the cable with a magnet, stainless steel is non-magnetic.

*Some* stainless steels are non-magnetic, others are magnetic.

is the problem in the chainstay or the cable housing between the RD and the chainstay? I tought you said the housing but everyone keeps focousing on the chainstay.

if your commuting in the rain and snow a good cable and some prevenative maintenance is your best bet.

is the problem in the chainstay or the cable housing between the RD and the chainstay?

After looking very closely, I now see the problem is at the point where the bare wire exits the chainstay and meets the housing. If I relax the shifter, the wire goes slack at that point and every point between the shifter and the final housing @ the RD.

is the problem in the chainstay or the cable housing between the RD and the chainstay? I tought you said the housing but everyone keeps focousing on the chainstay.

if your commuting in the rain and snow a good cable and some prevenative maintenance is your best bet.
That avatar doesn't look like any Bianchi I've ever seen.:D

After looking very closely, I now see the problem is at the point where the bare wire exits the chainstay and meets the housing. If I relax the shifter, the wire goes slack at that point and every point between the shifter and the final housing @ the RD.
Maybe your solution is as simple as a dab of grease.

Well, my LBS replaced the cable with a new stainless item and replaced the rear housing. $10.50, it was done while I waited and I was out the door in 15 minutes.

Well, my LBS replaced the cable with a new stainless item and replaced the rear housing. $10.50, it was done while I waited and I was out the door in 15 minutes.
Good testimonial for your LBS :thumb: