Was discussing this the other day with a friend. Basically he didn't know.

So how long do you expect a derailleur to last? (Assuming you don't bork it on a friendly rock)

eg, if you ride 4 hours a week and expect to replace it after 2 years = 2x52x4 etc

hours?

er

lots.

months worth in fact. Sometimes years.

Was discussing this the other day with a friend.

Christ, the hours must have flown by.

I've never worn one out. Few jockey wheels replaced, few seized up ones on seldom used bikes – quick spray of magic GT85.

LOLs @ Teh Tunstall.

"**** knows" is my answer, not long enough 😡

My 1997 Stumpjumpers XT rear mech and LX front mech are still going strong.

Replaced the jockey wheels on the x-9 on my newer (2007) Stumpy but it does much higher mileage.

I don't recall ever actually having worn one out either, although I have broken one. I've got a couple of old XTR mechs with very well worn jockey wheels which will need replaced as some point, but the mechs themselves seem fine.

A lot.

the less well known bob dylan classic.

I'd expect the casette and chain to wear out long before the mech ever does. Don't think I've ever replaced a mech and I reid for a lot more than 4 hours a week.

Good grief, we will be discussing MTBF numbers next….

http://en.wikipedia.org/wiki/Mean_time_between_failures

Was discussing this the other day with a friend.
Christ, the hours must have flown by.

lol

if you are really board you want to work out whether they are more molecules of water in teaspoon (5ml) that there are teaspoons worth of water in the Atlantic Ocean….

ragically1969 – Member
Good grief, we will be discussing MTBF numbers next….

Good idea 🙂

I tend to replace them when they go floppy (spring tension or around the parallelogram pivots/ corners) or are bent
I've had them last months or years depending on how much abuse (rather than mileage/ hourage) they get

I've had a jockey wheel last hours (destroyed the bearings in one at 10UTB) but as for mechs themselves if you don't break them they last years of normal riding

I have an old STX in the spares box, spring seems a little baggy but it still works, that's about 15 years old, not constantly in service but probably used for about 10 years total, so far…

Never worn one out, other than the pulley wheels.

Original rear mech still on my 1993 Dawes Roughtrade

never wore one out, broke a few though, like goldfish* they dont die of old age, they die of other things

*this may or may not be true

ripped one off within a few hours of having it. (booo)

they tend to wear at the pivots, and go rattly, creating vague shifting, but they still "work"

AAAAGES is my answer (assuming you dont rip it off)

If it's SRAM up until this year it will last anywhere up to 1 ride before the pointless and appallingly designed plastic inserts for the limiter screws fail. If it does last let's say up to 6 months it will develop significant play.

If it's Shimano it will last sometimes years and still work ok when it develops play and is a bit bent.

They go sloppy eventually and the shifting becomes a bit rubbish. I've just replaced one (XT) that's been on my bike since before I moved to the Alps.

Rough guesstimate it's done 2 summers of 5 days a week at, say 4hrs per day plus a bit more either side so something like 1,000hrs?

It was still working tolerably as well, just a bit wobbly.