Interesting Failure

[jbeattie]

So, I was riding to work this morning having trouble with front shifts, and then I just couldn't get the FD to shift at all. I figured my cable slipped, so I adjusted the barrel on the fly which helped a little, but not enough. I pulled the cable taut when I got to work and re-anchored it at the FD. Still didn't work.

Then I looked more closely and saw that the cable housing from my STI levers had exploded and that the cable and PTFE liner had puked out and kinked up the broken housing. I guess it couldn't handle the compressive force generated by my super strong shifts and exploded. I know I changed it out in the not too distant past. Oh well, I have plenty sitting around the house. This will make me spin on the way home.

-- Jay Beattie.

[Andre Jute]

Just don't ask fo advice on cables -- or you'll be told how to fix a toothache!

Andre Jute
If your only tool is a hammer, every problem looks like a nail

[Frank Krygowski]

On 4/28/2016 8:38 PM, jbeattie wrote:
> So, I was riding to work this morning having trouble with front shifts, and then I just couldn't get the FD to shift at all. I figured my cable slipped, so I adjusted the barrel on the fly which helped a little, but not enough. I pulled the cable taut when I got to work and re-anchored it at the FD. Still didn't work.
>
> Then I looked more closely and saw that the cable housing from my STI levers had exploded and that the cable and PTFE liner had puked out and kinked up the broken housing. I guess it couldn't handle the compressive force generated by my super strong shifts and exploded. I know I changed it out in the not too distant past. Oh well, I have plenty sitting around the house. This will make me spin on the way home.

That "exploding cable failure happened to that other friend of mine that
I described a couple months ago.

In his case, it was apparent that the plastic sheath (around the
near-longitudinal wires of the housing) had rotted. In his case, it
certainly had nothing to do with miles ridden or lots of force while
shifting. The bike was a basement queen.

I understand the value of the longitudinal housing wires. But with
helical housing wire, the plastic is just to keep the weather out. With
the longitudinal version, the plastic is structural.

--
- Frank Krygowski

[avag...@gmail.com]

Told this prior but...

Rode east n back into town on muh Raleigh. Made '78-80 had cleaned original cables not replaced

Rode into the US 41/COLONIAL intersection, the edge of town when Ford n Edison were here. The old bridge across the Chatahochee's not far.

I'm telekinetic. The immediate area around me is slightly different electrically than your space yet you share some telekinesis with me.

41 before Colonial was a movie set. 3-4 cars, the last a male Caravan were mating
piled onto a female roof back, were burned out, blackened silent, without glass ...

The Raleigh's shifting cable broke, followed by the rear brake wire.

A gas tanker came over the bridge at 3AM, driver fell asleep, rammed 3-4 cars at this light n exploded on a ball of fire.

[Peter Howard]

As you say, the plastic sheath on low compression shift cable is
structural and it does not take a lot of sun exposure to make it
brittle. Cold isn't an issue where I live but perhaps low temperatures
would not help either. I think that real Shimano cable housing branded
as such on the sheath is the most durable. I buy many meters at a time
from a reputable online supplier and if fake Shimano branded housing
exists I haven't been sold any yet. On some of my bikes, particularly a
folding recumbent trike and a folding real bike I slip a full length of
heatshrink tubing over the housing and shrink it down. If its the loop
that describes a full 180 degree bend from frame stop to derailleur I
install the loop in its final position before shrinking the tubing. An
added feature is that heatshrink comes in a number of pretty matt colors
and clear as well. The clear looks particularly nice.
PH