pdxtex

simple question. does cable housing ever wear out? i have the original housing on my commuter/rain bike (2001 trek 1000) and have replaced the cables tons of times but never the housing. would i benefit from new housing? rear mech still shifts fast and confident.

fietsbob

all depends.. simple answer ..

FBinNY 

Simple answer to a simple question; Yes definitely.

Housings wear out three different ways. The liner wears on the insides of the curves because of frictional wear from the moving wire.

Also the outer covers age through weathering, with exposure to UV from the sun, and oxidizers in the air. Eventually the covers break down which isn't so critical in brake housing, but can lead to the total breakdown of index (high helix) housing.

Lastly housings suffer the effects of everyday wear and tear developing kinks and bends or hyper extension (in brake housings only) all of which degrade performance.

relyt

My policy with shift cables and housing is never to touch them if they are working fine because tampering only makes things worse.

I replace my brake housing and cables yearly because unlike shifting, brakes are related to safety. Water can get inside the brake housing and corrode the metal spiral that holds the housing together. Not only does that weaken the housing, but it creates drag on the cable due to corrosion. It is so cheap that you might as well replace it when you do the cables.

AngelGendy

My 70's Ross still has the original housings......,

Al1943

STI shifter performance is a lot more sensitive to excess friction in cable housings. This can be caused by wear from the cable, dirt, cable oxidation, and other impurities. I recommend replacing the housings and cables any time there are symptoms of excess friction.
Replacing the cables and housings often restores shifting performance.
I think it is just as important to replace the housings as the cables.

Jeff Wills

+1. I replace my cables when needed and replace the housing about every third cable. It's a very noticeable improvement.

BCRider

Older housings such as from that era generally didn't have any plastic inner liner from the examples of old bikes that I've seen. As a result the cables run directly on the spiral wound metal compression liner. So yeah, the housings can last a LONG time. But I always found that even new cables didn't feel quite right in such housings. There's just more friction and catches in non lined housings for my tastes. So I tend to switch them over to new stuff with plastic liners and use smooth drawn cable. I just find that the resulting feel is far smoother and snappy.

Mind you metal to metal housings are prime candidates for greasing the cables. I have to admit that I never tried that option.

fietsbob

Index shifting is fussy , friction shifting much less so, typical issues are the ends.

fuji86

It's a tube, if they aren't damaged externally or internally binding, just squirt lube in there. If they are cosmetically ugly externally, that's your call to make too. The distance the cable travels inside the tube when the brakes are adjusted properly is negligible. Same holds for gear shifting, properly adjusted I don't think my brake cable moves more than 1/8-1/4" on a laterally & radially trued rim and how far can/do the front derailer and rear assembly shifter move.

jimc101

Yes, it can corrod as well, about a year ago, as I was riding my commuter, the lost the rear gears, when I stops, I found the inner cable had ripped through the outer casing, which had rusted through.

shelbyfv

I have found that the wires in shifter housing tend to become uneven at the ends so I make a fresh cut whenever I replace the inner cable.

Looigi

If shifting gets even a slight bit iffy, I replace the rear DR housing loop doing a careful job cutting the ends square with a cut-off wheel in a Dremel. Unless something else is wrong (rare), this always restores shifting to sweet perfection. Can't easily thread the used frayed cable through the new housing so I replace that too. From the LBS, the length of housing is ~$1 and the cable is a few $.

Shimano (105-DA) is more sensitive to this than SRAM equivalents.

Retro Grouch 

So what do you hope to gain by replacing the housing?

davidad

If it ain't broke don't fix it. If preformance goes down then replace the housings.