Bicycle Mechanics - stuck jammed internal toptube cable housing

Sigh. It never ends.
I am pulling a mixed Tiagra-Sora off a lovely Colango Olympic Master frame (it deserves better I figure.) and I have hit a snag.

The rear brake cable housing that runs through the toptube (in below front, out top rear) is stuck, seized, jammed. The snag has probably arisen at the front entrance point where the housing is bent, the metal spirals exposed and rusting slightly.

I presume I am dealing with a single length of housing (I have seen set ups where there are two separate pieces on either end but this seems solid). But from neither end does it more than barely budge.
I really really really do not want to break it short leaving me nothing to grab to extract it.

Has anyone faced this problem before?
Can anyone suggest the best way(s) to attack it?
is there any worst case scenario for extracting housing stuck inside the top tube?

thanks

Try LOTS of Kroil or similar penetrating oil squirted around both ends of the housing where it enters and exits the frame. Give it time to work and see if that loosens it up. Also, try pushing hard on the exposed ends to see if you can get them to move a bit. That's less likely to cause damage and snap the housing than pulling on it.

Also remove the setpost and, perhaps the fork, and see if the interior of the top tube can be accessed from there. Some frames have the top tube open at both ends and you may be able to work on it from there.

Also try threading the inner wire and pull it up to the head. That will allow you to pull on it while actually pushing from the other end.

if the Kroil doesn't work, put the bike in your car and park in the sun for a few hours with the windows closed. You might get it warm enough to soften or partly melt the housing coating.

Maybe you could try peeling the outer layer of the housing off one end or the other...

Day 2 of soaking in Liquid Wrench (we don't have Kroil up here in Canada unfortunately) and still no movement.
This is getting discouraging.
Peter

Interesting, found this post elsewhere (some other Canadian was trying to find Kroil) about the effectiveness of various penetrating oils:

"Some info from another forum that I found:

Penetrating Oils Compared

Machinist's Workshop magazine actually tested penetrants for break
out torque on rusted nuts. Significant results! They arranged a subjective

test of all the popular penetrants with the control being the torque
required to remove the nut from a "scientifically rusted" environment.


Penetrating oil .......... Average load
None ..................... 516 pounds
WD-40 .................... 238 pounds
PB Blaster ............... 214 pounds
Liquid Wrench ............ 127 pounds
Kano Kroil ............... 106 pounds
ATF-Acetone mix............ 53 pounds

The Automatic Transmission fluid (ATF)-Acetone mix was a "home brew" mix
of 50 - 50 automatic
transmission fluid and acetone.

Note the "home brew" was better than any commercial product in this

one particular test. A local machinist group mixed up a batch and all now
use it with equally good results. Note also that "Liquid Wrench" is about
as good as "Kroil" for about 20% of the price."

There is a home brew firearm bore cleaner known as "Ed's Red" that is equal parts Dexron ATF, Acetone, Kerosene and OMS that has proven very effective and much cheaper than commercial products when made in quantity. Serious target shooters go through a lot of bore cleaner so this cheaper version is worth the trouble to make.

I had a stuck housing on one bike I purchased - it hadn't been ridden in years. [Had a stuck stem as well.] Pulling on the housing just resulted in it coming apart, and I was left with housing inside the tube with no exposed ends to grab.

1. Soaked in the 50/50 mix for a couple of days. After extraction I'm really not sure this helped much, as the outside of the housing appeared relatively dry, but it didn't hurt.

2. Used a spoke to stick down inside the tube and thread into the housing. I don't recall if it was a 14g or a 15g spoke, but one size worked much better than the other.

3. Grabbed onto the spoke elbow with a large pair of vice grips and pulled. I pulled out short sections twice (desinegrated) before the rest of the housing pulled free. :beer:

IIRC I thought about using a cable w/end and trying to pull it through - but I was worried that I was just going to compress the housing further inside the tube - so I don't think I gave this a try.

good suggestion.
How much housing was exposed on the end where you inserted the spoke? I presently have about 8 inches showing and that is longer than my spoke. I might have to cut it down.
I am also looking for a slim (like 1/8") thin long flat blade of some sort that I might be able to slip between the channel wall and the outside of the housing and jam around and loosen the snag.

good suggestion.
How much housing was exposed on the end where you inserted the spoke? I presently have about 8 inches showing and that is longer than my spoke. I might have to cut it down.
I am also looking for a slim (like 1/8") thin long flat blade of some sort that I might be able to slip between the channel wall and the outside of the housing and jam around and loosen the snag.


I had no housing exposed. I had pulled on the exposed portions until they ripped off. :crash:
You're screwing the spoke into the end of the housing to give you something to pull against. It should be a tight fit.

Phew!
My friend and local amateur frame builder Olivier A. came over last night. After 20 minutes of study under a bright light he slipped a piece of cable into the housing and grasped the bent end -- housing and cable -- and tugging and twisting gently got it to move and slide out.

I think the key was having the cable inside as reinforcement. INdeed as I think about it, if the cable is solid, Visegripping it on either end, there is no way the housing can snap. and if the cable moves, the housing has to go with it.

On examination it looks like the metal spiral of the housing had separated and had expanded in diameter slightly under the plastic coating and had friction jammed in the channel- like a blocked artery.

Lesson I guess. Grease your housings well.