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PotomacCyclist
09-03-2013, 01:27 PM
I was doing a race-pace workout the other day when I felt a sharp edge on the left bar end shifter (at the end of the aerobar extension). When I checked it out at home, I saw that some of the strands of the cable had slipped out of the shifter although the shifter was still working normally. I know that I need to fix it eventually. But I've read that if you replace a cable, it takes some time for everything to settle in. I have a race coming up in a few days (the Nation's Triathlon) so I don't really have time to let a new cable settle in.

I know it might be difficult to diagnose this over the Web, but do people think that I could just put some sort of tape over the loose ends of the cable and go with that until the race? The shifting doesn't seem to be affected for now, although I'll test it out again today. The only issue is that the ends of the cable are sharp. If I cover it up with electrical tape, then that wouldn't be a problem for the next few days.

Is there a risk of the cable detaching completely from the shifter, thereby preventing me from shifting the front derailleur? While this wouldn't be catastrophic, it might be a minor annoyance. If this happened, I would try to keep the chain in the big ring and just shift the rear derailleur. There aren't any big hills at the Nation's Triathlon. Some moderate ones, but I think I could deal with being stuck in the big ring and downshift on the rear cassette. That might put some minor strain on the chain, from cross-chaining, but that would only be for brief intervals. After the race, I won't be riding the tri bike as much for the rest of the year. I'll probably get a new chain and maybe a new cassette by the spring anyway.

I looked up info online but didn't see too many relevant search results (before anyone says "Google is your friend").

Tim Kelley
09-03-2013, 01:46 PM
Post a photo.

If you replace the cables, it takes awhile for them to stretch. Shifting should be fine immediately after replacing the cable, but will slowly get out of tune (think 100-200 miles worth of riding before you start having some stretch).

hozn
09-03-2013, 02:01 PM
What Tim said is ideal (post a photo). I don't have any familiarity with bar-end shifters -- specifically how the cable is anchored to the shifting mechanism -- but I probably would be inclined to just leave it if it was only a strand or two of cable that seems to have "broken off" there. The only thing to be careful of with electrical tape is the sticky residue that it leaves behind; again, not sure what this looks like, but if there is danger of the sticky stuff making contact with the cable where it enters the housing, this might interfere with smooth shifts (and persist as a problem even after you replace the cable). Again, I'm probably imagining this wrong :)

It does take a little while for the cable housing to compress (which gives the illusion of cables stretching), but I would still be nervous about replacing a cable *right* before an event. If you have the opportunity to spend a 2-3 hours on the bike beforehand, then you'd probably be just fine replacing it now and dialing it in on the bike. You may have to tweak the tension a little after a few weeks of riding, as Tim notes, but that should be relatively minor. (I suppose it depends on the housing you use; I use compressionless housing everywhere, so I don't deal much with "cable-stretch" issues, but it still often takes me a few rides before everything is adjusted to my liking.)

americancyclo
09-03-2013, 02:05 PM
I use compressionless housing everywhere, so I don't deal much with "cable-stretch" issues, but it still often takes me a few rides before everything is adjusted to my liking.)
Maybe you mentioned this elsewhere, but what cable housing do you use? Same for brakes and shifters?

off2ride
09-03-2013, 02:09 PM
Actually it's not the cable that settles in. It's the cable housing that settles in the ferrules. No need to settle the housing if you're only replacing the cable. The housing's already set. All you need to do is tweak the adjustment. IF you're replacing cable's and housing, cut the housing to desired length, make sure the curves are not too tight but not too long either. Thread the cable and secure it to the derailleur. Here's where a sturdy stand comes into play. If the cables are NOT internal you can push down on the cables on the down tube by hand while you're pedaling with the other hand. Give it a nice push for about 10 seconds or so. This action pushes the housing ends into the shifter body and the other ferrules. You might have to push more than twice to get a good seat. One you think it's in there, tweak the derailleurs. I also do the same when replacing brake cables and housing. Good luck.

hozn
09-03-2013, 02:11 PM
Maybe you mentioned this elsewhere, but what cable housing do you use? Same for brakes and shifters?

Yeah, I use this stuff: http://www.jensonusa.com/Jagwire-Ripcord-Universal-Housing

I became a convert based on its performance on my disc-brake mountain bikes. Probably overkill on the road bikes ... but I had 25 feet to use up ... :)

Only disadvantage is that it's thick (5mm) housing, and the ferrules they provide don't always fit in places that expect derailleur ferrules. I seem to have a big collection of different size ferrules, though (e.g. some that taper down) so I haven't had a problem in practice.

APKhaos
09-03-2013, 04:14 PM
Replacing the inner cable avoids the settling that [as off2ride said] is due to the new outers snugging into the ferrules.
New inner cable, tune the deurallier, you should be good to go!
Alternative is ride with a couple of frayed strands, especially if they are not bothering you. Chances of the cable failing are slim. Feeling lucky?

DismalScientist
09-03-2013, 04:23 PM
This is a front derailleur cable so settling in is not an issue as it likely is non-indexed. If your front is a double, use the limit screw to control the extremes of derailleur movement. As everything settles in, there will be minor adjustments to trimming the derailleur depending on which rear cog the chain rests. In other words, just change the cable and you won't have to worry about it breaking.

PotomacCyclist
09-03-2013, 04:28 PM
3625

You can see the strands on the bottom of the shifter in this photo. When the shifter is in the down position, it's not a problem. When I pull back to shift to the big ring, then the strands get forced outward. That's when I have to be careful not to hold onto the strands.

If the chance of the cable failing is slim, then I'll probably wait on replacing it until after the race. But I will still need to put something over the frayed ends in the meantime. Those ends are very sharp. If I accidentally grab onto them (which could happen in the middle of a race), I could cut my fingers. (I'm not a fan of staph infections.) If I were going to replace the cable later on, residue from electrical tape shouldn't be a problem. Or am I overlooking something? I'm not much for DIY bike repairs. I limit myself to chain cleaning, tire inflation, tire replacement and safety checks. If other work needs to be done, I let the bike store people take care of it.

hozn
09-03-2013, 05:37 PM
I think my electrical tape caveats don't apply here. It's really hard to say what the likelihood of failure is. If you have time to ride it beforehand, I would say replace it. If not, though, probably leave "working" alone?

papalena
09-03-2013, 07:12 PM
You can see the strands on the bottom of the shifter in this photo. When the shifter is in the down position, it's not a problem. When I pull back to shift to the big ring, then the strands get forced outward. That's when I have to be careful not to hold onto the strands.

If the chance of the cable failing is slim, then I'll probably wait on replacing it until after the race. But I will still need to put something over the frayed ends in the meantime. Those ends are very sharp. If I accidentally grab onto them (which could happen in the middle of a race), I could cut my fingers. (I'm not a fan of staph infections.) If I were going to replace the cable later on, residue from electrical tape shouldn't be a problem. Or am I overlooking something? I'm not much for DIY bike repairs. I limit myself to chain cleaning, tire inflation, tire replacement and safety checks. If other work needs to be done, I let the bike store people take care of it.
I have bar end shifters on my bike as well, and have encountered this same problem a few times (although only with the cable to the rear derailleur, never the front. yet.) I don't think the electricians tape will hold the broken wires back very well or for very long (as you say, the wire is pretty stiff). My attempt at a short term fix involved clipping off the ends sticking out with diagonals (wire cutters), which can work for awhile if you can cut them really close to where they begin to stick out, and make sure that the remaining wires don't get caught in the cable housing. Even if you're successful, more of the wires will soon break and you'll start getting sliced by them. (If you think about it, it's an unstable situation: the fewer the remaining wires, the higher the tension on each of them-- and they will start breaking sooner.) Given this experience, I now replace the cable as soon as possible to avoid the otherwise inevitable finger punctures.

PotomacCyclist
09-09-2013, 06:09 PM
I think I figured out why it happened. I went a little too long before cleaning/lubing the chain and derailleurs. I noticed that the front derailleur was very difficult to shift in the week or two before the wire started sticking out. I upshift the rear derailleur before shifting to the big ring in front, so it wasn't an issue with cross-chaining. More like an issue of dirty bike parts that needed cleaning.

I had to crank back on the shifter pretty hard for a couple rides. That's when it happened, and the wires began peeking out mid-ride.

Anyway, the shifter and cable held up well during the race. Unfortunately the engine (i.e., me) didn't fare quite as well. I finished but with a bit slower time than I was expecting or hoping for. (Plus my swimming continues to be sub-par this year. Even more than last year. I need to fix this over the winter too.)

hozn
09-09-2013, 06:47 PM
Congrats on finishing; sorry it was slower than you hoped. But, yes, there's always next year!

Perhaps you need to replace some of the housing or cables if the interface is starting to corrode.

PotomacCyclist
09-09-2013, 10:27 PM
I'll continue to ride the tri bike for a few more weeks, mostly to rack up more miles for the National Bike Challenge. (Maybe some easy but long weekend rides on the remaining weekends in September, along with shorter weekday rides. Not training-related. Just to get the miles up while decreasing intensity. At the same time, I plan to ramp up my running since I'm going to do the Army Ten-Miler in October. Mostly for fun, but I'd like to be in decent shape for it.)

By Nov., I'll probably stop riding the tri bike for the year and switch to a combination of mountain, CaBi and spin bikes. Then I can wait until late winter to have the cables replaced at a bike shop. The problem will still be there, but it won't bother me because I won't ride the tri bike at all over the winter. In the unlikely chance that I decide to get a bike trainer, then I would get the cables fixed. But I'd say there's about a 10-20% chance of me getting a trainer. Just doesn't sound like much fun. If I'm going to ride indoors, I can just go to the gym and use a spin bike.

As for the race, I wonder if I made a mistake in taking a CaBi bike to the transition area on the morning of the race. While I tried to coast as much as possible, to minimize energy expenditure pre-race, it was still 25 minutes of riding. I had a couple Clif bars beforehand (almost 500 calories), but I didn't eat after the CaBi ride. I actually swam straight, maybe for the first time ever, but I might have been overly cautious because of my DNF at a tri swim back in June. So I was out in the water much longer than expected. I felt kind of sluggish on the bike, maybe because I was running low on glycogen. The CaBi ride could have played a part. I had Clif Shots carb chews. The time wasn't horrible compared to previous years, but it was definitely slower, on the swim, on the bike and on the run.

I did a planned short bike/run brick on Saturday. But I also rode to the bike check-in and rode back on CaBi. So that was two more bike trips added to the brick workout on the day before the race. I have to be a little smarter about that in the future.

Anyway, I'll be back next year. I'm not sure which races, but I will include the Nation's Triathlon as usual. Other races and events too. (Tri, bike, run. Probably no stand-alone swim events but who knows? Maybe I'll suffer from temporary insanity and sign up for a medium-distance open water swim, like the Swim Across the Potomac: Old Town to National Harbor.)