I set out this morning on what was intended to be a 50-mile ride (first one this year, for me). I was prepared with the proper balance of stuff to eat to keep going past mile 35, which in my hilly area is about the point at which I need to have been consuming food all along or I'll bonk somewhere around 40. Extra tube, check. Small road cycling pump, check. Patches just in case, check. Small multi-tool, check. 48 ounces of fluids, check (I can refill along the route).

At mile 24.9 I had a goathead puncture flat. No problem -- that seems to happen to me every other week lately. I even had some CO2 with me so that I wouldn't have to do the 320 strokes it takes with my small pump to get me back up to 100PSI (GP4000II 28mm tires take a lot of air volume). I walked a tenth of a mile with the bike to a more pleasant place to sit and work on the flat.

After getting the tube swapped out I downshifted to the smallest cog to make it easier to re-mount the rear wheel. Installed the wheel, re-set the brake... then it happened.

I lifted the rear wheel off the ground and started downshifting while spinning the cranks to get to a gear more appropriate for starting off again. *SNAP* the rear derailleur's cable broke right at the brifter. There I was, exactly 25 miles out in rolling-hills terrain, with about 1200 feet of elevation gain, mostly in an intense three mile segment between me and my home, and stuck in the smallest cog.

I rode about a mile and a half to a reasonable pick-up point and got ahold of a friend who was about to take his lunch break at work, a quarter mile away. Got a ride to the bike shop in my own neighborhood, and they replaced the cable in under five minutes. I rode the rest of the way home and finished up at 30 miles, instead of my intended 50.

Lessons learned:

• Over the past couple weeks I've been adjusting my RD constantly throughout my rides. It was seeming harder and harder to reliably upshift and downshift through the entire cassette from both chainrings. I could get things set fairly well for one chainring, but would have to re-adjust my RD a little when in the other chainring. I had a feeling that either a cable was getting bad or the shifter was wearing out (Shimano 105). But rather than taking the bike in for work I rode hundreds of miles with this annoyance until the cable snapped, 25 miles from home. Next time I'll pay closer attention to what the bike is trying to tell me.
• Most of the time I don't bother bringing my phone with me. People rode bikes for 180 years without phones, after all. But for 120 of those years pay-phones were a thing. Not so much, anymore, in my area. I had my phone with me this time. And I will bring it with me in the future.

Questions:

• Do road cyclists carry an extra shift cable typically? My seat pouch is already pretty full with a tube, CO2, tire levers, some candy for last-resort, stick-on patches, and a small multi-tool. I might be able to find room for one... maybe. But what else? After flat tires what is the next most common thing that I maybe should be prepared to deal with?
• If I do start carrying a cable, are brake cables and shift cables the same style cable? Do I now need to also start carrying a wire cutter, termination crimper, and so on?
• ...or do I just rely on the phone on those infrequent occasions where something like this happens?

The cable that went bad probably had 4500 miles on it. In those same 4500 miles I've replaced my chain twice, my rear cassette once (mostly to get a different gearing), my saddle, my bar tape, my stem (as part of a fitting)... and that's about it. The rest is original equipment.

Anyway, to me the most important take-away is to pay attention when the bike starts getting flaky. When it started becoming increasingly difficult to get the RD adjusted properly, I should have investigated the cables.

In the end, it was still a good ride, though I would have preferred to ride the whole way back under my own power.

By the way, if anyone here cycles near the east bench in Sandy, Utah, if you find yourself in need of service, Salt Cycles is great.

I inspect my cables periodically and change them out as needed. And no, extra shift cables are not normally carried around.

Never carried a spare cable, I can ride my bike without one. If you have a chain tool, and I always do, you could have turned it into a single speed in an easy gear. Just bypass the rear derailleur and wrap it around the small ring and cog of your choice.

Each time I've snapped a cable I've had the same issues during previous rides. I'd think by now I'd recognize the pattern in time to predict the impeding doom, but nope, not yet!

For me there is no inspecting, investigating or waiting for symptoms.

My mechanical bikes are changed proactively every 2500 miles or about 2x/year. 4500 miles on cables is too much.

In summer the inner wires are changed and in winter the housings are replaced as well. Changing cables and housing is an opportunity to inspect the bike and perform maintenance on everything else - make sure the headset is tight, replace pads if needed and adjust brakes, torque seatpost/stem/cranks, etc.


-Tim-

Same thing happened to me a few weeks ago though I was only 5 miles from home. Trouble with a spare cable is both times this has happened to me in 11 years, getting the broken part out of the shifter is a major ordeal requiring tools that I do not carry on a ride (and tools you cannot predict needing until you can see how it is broken). Just depends on where it breaks and shifter design. I would shorten the chain to a SS before trying to replace a cable on the road. I carry a spare Wipperman link for such breakdowns and any other chain issue that might require it.

Don't carry a spare cable, but I have managed to get the derailleur into a more usable gear. One way is to screw in the high limit screw so the der. is prevented from shifting into one of the smallest cogs. Another option is to manually push the der. inward and then wrap and tie the remaining part of the cable (unless it snapped at the der.) around some part of the bike so it can't move. Either way you now have a 2 or 3-speed bike (depending on whether you have a double or triple chain ring) which is usually good enough to get you home

A broken spoke would be the second most likely issue, in my experience.

I always have a key with me to semi-true the wheel with a missing spoke.

That's a great idea ... so, you just wrap it around the ring? No need to fasten or clip it (sorry, probably dumb question)?


I had a situation once where my cable snapped, the chain hopped off the gear and sliced into my seat stay, making a crease, but not breaking through the (aluminum) frame - just a couple miles from my car. Fortunately, the frame was still safe to ride, and I did for a couple more years before relegating it to my winter/bad weather bike.


Since then, I'm just more proactive about having the cables changed by my LBS ... definitely not more than a couple seasons on my main road bike - or maybe when I'm making the 2nd or 3rd chain change. (to OP, I don't carry a spare cable - the risk is too infrequent IMO to be bothered and I'm not skilled enough yet to change cables anyway).

This thread now has me concerned. My road bike is in its third season. Cables have never been changed.

Then you have to replace the chain, and a $2.00 repair turns into a $30!

I would never do that.

All you need to do is either pull the cable taut to where it stays in an easier gear and wrap the other end around a bottle cage or something, or if the cable breaks at the derailleur, just pull the cable out and set the limit screw to an easier gear (won't be as easy a gear as you can get with a cable).

Takes all of 3-4 minutes and no destroyed chain needed.

Yep. If you're constantly having to tighten the cable housing to keep your shifting decent, then the cable is likely fraying and about to snap.

Like [MENTION=107711]datlas[/MENTION] said, recognize the signs of a fraying cable. I assume that we're talking indexed shifters. Anyway, a good tuned system will start making ragged shifts like the rear derailleur just needs a little tweak as [MENTION=426467]rubiksoval[/MENTION] mentioned. It will quickly get worse. Like mentioned earlier, shift sparingly and head for home.

You don't have to replace the chain.

Breaking a chain, taking out links, rebreaking the chain, adding links...

You'd be a real fool not to. But it's pretty foolish to do what you suggested in the first place, too.

Anywwy, a great example of what not to do.

I have to wonder how much weight it would take to snap a typical bike shifting cable? We have to be talking at least several hundred pounds.

So OP, if you are breaking cables that ought to outlast the rest of the bike (assuming they don't get rusty) something is clearly wrong in your setup. Cable routing being the most likely culprit. I would overhaul your cable and housing and try to figure out where the cable is binding or whatever it's doing.

It's not normal to go through shift cables so fast, and whatever the problem is, it's probably compromising your shifting performance too, so definitely look into it. I would go as far as to replace a brifter if that was the problem, this is serious ****.

Total ignorance. You have absolutely no clue what you're talking about. None. Why do you think Shimano sells replacement pins? Why are replacement quick links sold? Why is it in 31 years I have never had a chain snap on me after I replaced those things countless times?

Snapping a cable = reconfiguring your chain. Yeah, you're a bastion of competence.

YMMV, but I have NEVER had problems with brake cables. They are thicker caliber and likely will last many seasons.

Similarly, I have never had issues with FD cables. I probably switch mine out every 3-5 years but they also last a long time (for me at least).

But the RD shifter cables, especially Shimano under-the-bar tape ones, seem to break more often. I only get 2500 miles from mine as above.

BITD of DT shifters, the RD cable would similarly last for many years.

As always, YMMV.

You're a complete newbie and the OP would be smart to listen to nothing you say. You're a bastion of incompetence. Taking 2 minutes to "reconfigure" your chain so you don't have to call for a ride like the OP did? Yeah, stud.

Explain why these are sold.

I don't carry cables on my rides. But I do transport them in a mini tool box when I take a cycling vacation.

You just jogged my memory. I think I did have my RD cable replaced this spring. It was shifting funny. Brought it to Bikesmiths and they found it had partially torn away from the stop inside the shifter. I think I forgot because normally I only let Wissahickon work on my Engin and hadn't been there for anything but the hub warranty thing in a while.

it's got me thinking too .. my rear brifter has been a bit cranky for a while now ...