stevage

Just back from a 4 day tour on which two (XT) rear derailleurs were destroyed. In both cases, we were able to *just* patch them up to be rideable. One was a work of art, with gaffer tape and cable ties holding together bits of derailleur cage that had snapped in half.

But these were essentially trip-ending mechanicals for both riders. If we'd had spares, both could have continued rather than limping to the nearest train station. I've personally broken a RD on two previous trips - so that's 4 RDs out of about 30 trips I've been on.

Is there such a thing as a lightweight spare derailleur? Anyone ever carry a spare? I'm starting to think that for bigger trips (10+ people), carrying a spare for the group would make sense, especially since almost everyone uses 9 speed.

bikemig 

Love it. What kind of tour are you talking about? Was this offroad? I've never destroyed a derailleur on a long road trip but offroad is a whole different story. For a group of 10+ people, spare parts make sense.

digibud

I'd be curious to learn how the derailleurs were destroyed. I've never destroyed a derailleur. Oh...not true. I had a chain break and wrap up into the derailleur which destroyed it. On tour that would have been an end until I got to a shop. That's once in many thousands of miles of travel. I'd sooner expect to have a bearing failure lock up a wheel or a cable fray and break or something. For me, a broken derailleur is too rare to plan for. I might take along a spare dropout. Bending a dropout is reasonably common. A spare rotor even.
So what happened, if I might ask?

MMACH 5

And I gave my buddy grief for breaking two chains in one trip. He claimed it was because he was too strong for mere steel.

There have to be some good stories behind breaking your derailleurs.

3speed

I'm also curious as to the situations in which the RDs failed. I'm not at all doubting it can happen. It just seems to me like you've had a run of bad luck(or the people you're riding with). I've crashed my mountain bike multiple times, and know others who have also, and never managed to break a RD. Bend the hangers, yes, but not the derailers. I did manage to break one due to it getting Packed with mud and the chain bound up in it, but it was an old worn out derailer that barely worked right or shift very well to begin with because it was so worn out and I kept riding even knowing it was having problems. I don't really count that one.

Anywho, I could see taking a spare derailer on a longer ride involving 4+ people or so. Maybe some other spare parts too. Each person could take a couple parts "just in case" and it wouldn't cause any one person to carry too much more weight and would keep the group prepared.

indyfabz

Another one in the curious camp? I rode across the country with 12 people. That represented over 57,000 bike miles. Not one busted RD. Have done several other month+ tours and other shorter ones. Never injured a RD while on tour.

I destroy one once, but that was because my hanger was bent. I knew it and was too lazy to get it bent back into shape. While on a training ride, on a steep hill, I decided to see how low my granny gear was, forgetting about the bent hanger. The RD cage went into the spokes and asploded. Fortunately, I was only a few miles from home.

And if your friends destroy normal RDs with regularity, how durable do you think a light weight one would be?

skilsaw

My wife shifted her RD into her spokes at the bottom of a very steep hill. I must have had the limiting screw adjusted poorly for that to happen.

My guess is poor maintenance if RD's are breaking often.

prathmann

I'm also in the camp of not considering carrying a spare although I did once destroy mine on a tour. My own fault - was trying to fix a flat without bothering to remove the loaded panniers and apparently got the chain twisted so when I tried to start riding it ripped the RD to the side. It was the last day of a tour and I was able to get home by selecting a moderate gear and just riding as a single speed. But if it had been in the middle of a tour I'd think a visit to almost any bike shop would have allowed the tour to continue and bike shops are usually easier to find than train stations. I could see carrying a spare hanger, especially since those are bike make/model specific so it might take a shop a while to get the right one.

Assuming that everyone uses 9-speed wouldn't apply for me. The bikes I currently use for touring are 6, 7, and 8-speed respectively - but the shifters can all be switched to friction mode so just about any derailleur should work ok.

Sixty Fiver

I smashed a derailleur into a rock once while I was off roading and had an XTR blow it's tension pulley while I was walking my bike... that is the only rear d failures I have experienced in 30 years of riding.

BohicaX

I have had derailleur's fail but I was lucky because I carry the spare parts on me. What failed was the tension spring over time they loose the ability to keep tension on the chain and while you can pull them apart and place the spring in the second hole to give more tension that had already been done so the spring was at life's end when it gave way. The other parts that that I carry is a small plastic seal that keeps all the crud out of the tension spring housing and an o-ring that goes on the derailleur cage that the tension spring goes over to make a seal on the other end that the grub screw holds it all together. I also carry a spare derailleur hanger and alignment tool plus a set of jockey wheels but only because my tours end up being years long.

fietsbob

<Knock wood>, nope, but My touring pace is Plodding , and it seems the panniers

do a good job of letting me lay the bike down without hitting the derailleur.

perhaps the light weight was the problem, a mis application of race level gear, IDK.

I got Campag MTB derailleurs on close out** in the 80's they did not try for light weight on those.

** The company ceded the MTB sector to the Japanese companies .. and got out.

BigAura

If you're planning on carrying every part that might go wrong on a bicycle you might as well carry an extra bike Although I believe in Murphy's Law, it's application as relates to spare parts is useless.

nun

Derailleur failure is not common and should not stop you from making it the next bike shop for repairs so i wouldn't carry one on tour. If the derailleur does break just take some links out of the chain and ride singlespeed.

stevage

Sorry, I should have known people would want to know

1. "Just riding along" on an old mountain bike, on flat, sealed road, when ka-blam. A jockey wheel dropped out and was never seen again. Probably the screw that holds it in got loose and fell out. (Managed to hitch hike back into town where a bike shop was improbably open on Easter Sunday)
2. Riding off road along 4WD tracks, hit a small twig which broke the derailleur hanger. (Come to think of it, the derailleur itself was probably ok. We turned around and rolled all the way back downhill to our starting point, with a bit of towing for good measure, then bailed out. I carry a spare hanger now.)
3. Pushing along a sandy 4WD track, he hit "something" which both smashed his derailleur to bits, and cracked a bolt that holds his wheel on. (It's some weird skewer-less arrangement.)
4. Riding down a rail trail covered with a lot of twigs and branches. Not sure what happened exactly but the chain broke and the derailleur ended up badly bent, with a couple of jockey wheel teeth snapped or bent. Probably she hit a branch. (We were two different groups intending to meet up in one place, but altered our plans to meet up, fix her bike and ride out together.)

I agree that on sealed roads it's incredibly rare. But sealed roads are boring.

stevage

>If you're planning on carrying every part that might go wrong on a bicycle you might as well carry an extra bike

Well, sure. I do carry quite a few spares though: tubes, spokes, derailleur hanger, brake cable, gear cable, bolts, chain links, etc.

stevage

>Derailleur failure is not common and should not stop you from making it the next bike shop for repairs so i wouldn't carry one on tour.

That might work on longer trips through populated areas, but wouldn't really apply for me. Most of these trips are 3-4 days, start and end in large towns on train lines, and don't pass through any major towns. So generally the "next bike shop" is at home.

I'm not worried about being stranded and unable to get home from somewhere - I'm worried about the whole trip basically being over because of one mechanical, which is what usually happens.

> If the derailleur does break just take some links out of the chain and ride singlespeed.

Yeah, it's a nice idea in theory, it never seems to actually work though. It's really hard to get a perfect length of chain that will stay in a gear combination without trying to climb up or down. Maybe with horizontal dropouts you can do it, but we've never had any success.

BigAura

I've limited my spares down to: one tube, FiberFix spoke, chain quick-link. That covers the three most common failures you're likely to run into on a tour.

Of course I do carry general purpose repair items: patch kit, tie wraps, and duct tape. These can also be used to make camping kit repairs.

djb

*first of all, "touch wood"

your first example (straying jockey wheel) shows the importance of frequent chain oiling/cleaning/overall keeping an eye on your bike. I know Im a bike nerd who actually enjoys mucking around with the bikes in my family, but the bonus is that when I quickly wipe down my chain with a rag, and do the jockey wheels while Im at it before relubing the chain, it means I'm pretty familiar with the drivetrain and hopefully would notice if stuff is getting loose. Putting a bike up on a stand once in a while is good too for seeing how hi and low screws are doing, and/or being attentive hearing-wise for shifting.

all that said, your off road trips are always going to have the possible factors of crashes or folks riding into hard stuff or whatever with the rd. Makes sense for a spare hanger (specific to ones bike) and it does make sense for a group ride, given your past experiences mentioned, to throw in a used rd, or at least a cheap one. The idea of spreading spares around people sounds good. Up here, a med quality rd can prob be found fairly cheapy, the prices in the States are even less, so I guess the weight factor really isnt an issue between models (we are talking grams here arent we?) but the cost diff could be great, especially since you know that if you buy a top model rd and carry it with you, Murphy's law will mean you'll be carrying that $175-$200 around with you unused for decades.....
Id go for cheapie.

rodar y rodar

I would have said that I`ve never had a derailler fail instantly either, but this jogged my memory- the same thing happened to me

In my case, it was also an old derailler (early Deore, very shiny and pretty), and I was also JRA, but right in my own town. Mine resulted better, though. The chain first got really noisy for a few seconds, probably when the threads came out of their hole and let the jockey wheel cock to one side before falling out. So I stopped pedalling and looked back, and it finished the job while I was slowly pedalling forwards and backwards trying to figure out what the deal was. Since I was nearly stopped by then, all the pieces were easilly recovered.

Anyway, I`d never consider going to the extreme of carrying a spare myself, but if I had your history of derailler deaths, I would be singing a different tune.

stevage

Yep, but actual spokes, spare cables etc are really light. I started with the cables by accident - I had bought a gear cable and it just happened to be in my pannier. Two hours into a cycle tour, my partner's cable frayed and snapped inside the STI shifter. Having the spare cable and a pair of pliers meant a brief repair job, then completely fixed - rather than spending hours limping to a bike shop, having to change route, or even abandoning the trip. Totally worth it.
Oh yeah. Gaffer tape, cable ties, wire (very handy), safety pins, dyneema cord. Again, all extremely lightweight but useful.

stevage

Yeah, it's surprising how cheap the cheap ones can be. When I had that jockey wheel failure (many years ago, much less experienced), I was working out in my head how much I'd be willing to spend to keep going on the trip. I thought something like $100. The derailleur ended up costing $10, plus $10 labour. Ridiculously cheap.

OTOH, it was still only moderately rideable, as it was an 8 speed RD on a 7 speed drivetrain, but since the terrain was flat it easily got me home.