• This topic has 31 replies, 23 voices, and was last updated 3 months ago by irc.
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  • Rear mechs – do they wear out
  • Premier Icon ayjaydoubleyou
    Free Member

    I’ve got an XT (10 speed) thats probably 4-5 years old.
    The bike (it’s on its second bike actually) gets thrashed as much as my skill level allows.

    Despite new chain and cassette and chainring and jockey wheels (15-20 rides ago), the shifting is still sometimes a bit off, catching on the next gear, refusing to go down, ghost shifting.
    I dont think its the cable, as it seems to run smooth at least some of the time, and behaves perfectly when fiddling at home.

    I also drop chains occasionaly despite having a top guide and a relatvely new narrow wide ring. I’m tied to raceface due to cranks sadly, I like the look of the tall toothed sram offerings.

    Do mechs get baggy, tired, sloppy whatever? Is it repairable or terminal?

    For reference, similar set up, of similar age on my hardtail which sees more miles, far more mud, but far less gnar and due to terrain, probably less shifting per mile; is perfect and buttery smooth in comparison.

    Premier Icon scotroutes
    Full Member

    Well, they can…. but have you checked hanger alignment?

    Premier Icon chrishc777
    Free Member

    4-5 years?! Yeah time for a new one, they get sloppy and while it may not have bent out of shape on one knock it has probably seen lots of small impacts that bend it out of shape in all directions

    The clutch is probably completely knackered as well, those 10 speed ones were never great

    Mine usually last about 6 months

    Premier Icon ebennett
    Full Member

    I had an eagle mech develop play in the parallelogram after ~2 years of use which resulted in poor shifting, so I’d say yes they can. However, none of the other ones I’ve had ever lasted long enough to develop it before getting smashed off by a rock…

    Premier Icon Onzadog
    Free Member

    Do rear mechs wear out? To yes, if you look after them. If you don’t, they’ll normally get destroyed before then.

    Premier Icon honourablegeorge
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    My XTR 11s sas on its’ third bike, had it since 2013 or thereabouts, but let me down for the first time last weekend. Serviced the clutch and got it back to 90% of former glory. Only just took it off to fir 12 speed. Not a bad innings.

    Premier Icon p7eaven
    Free Member

    Some more than others. But all will get sloppy at the end of that (equal to a piece of string) length of time.

    I’ve always dismantled and cleaned the jockey wheels from time to time. Clean and grease the mech if was clogged. Never had one wear out as such before changing bikes. I’m sure someone with even moderate engineering p/mechanical skills could make a basic derailleur last almost indefinitely with regular servicing/replacing jockey wheels etc.

    Premier Icon matt_outandabout
    Full Member

    Have you changed jockey wheels?
    Have you given it a wobble? (Shimano are usually pretty ‘solid’ feeling, SRAM have a ‘deliberate’ wobble from new…)
    Is the clutch/tension spring still strong?

    Premier Icon ayjaydoubleyou
    Free Member

    Not checked the hanger (dont have the abiltiy to check, but have a spare I can try)

    New jockey wheels last summer – fancy hope ones, no play

    Serviced the clutch and got it back to 90% of former glory

    Is this simple-ish to do, or is it a full garage workshop type endeavour?

    Clean and grease the mech if was clogged

    Is this dissassembling, or just spraying/lubing the obvious moving parts?

    Is the clutch/tension spring still strong?

    Notable differnece between clutch on and off, but probably not as strong as others I have seen.

    Premier Icon honourablegeorge
    Full Member

    ayjaydoubleyou

    Is this simple-ish to do, or is it a full garage workshop type endeavour?

    2mm allen key, some brake cleaner, some grease. You don’t want drop the little screws and lose them, so don’t try doing it on a gravel driveway or a deck with slots in it:) Video below.

    Notable differnece between clutch on and off, but probably not as strong as others I have seen.

    Sminao clutches are adjustable, so you can make it firmer, video will show that also

    Premier Icon vmgscot
    Full Member

    GMBN Tech show (youtube) did a recent video on servicing your mech (including clutch) – maybe worth a watch?

    Premier Icon scotroutes
    Full Member

    Not checked the hanger (dont have the abiltiy to check, but have a spare I can try)

    Your spare is just as likely to be bent. A proper tool is one of the best investments you can make.

    Premier Icon susepic
    Free Member

    Ghost shifting, if it is on a full sus, might be that the cable is too short and tension changes as the suspension compresses. You might want to add a little slack in the cable and outer length to sort that out. Also worth looking at B-screw adjustment to ensure enough clearance on the cassette

    Premier Icon Aidy
    Free Member

    Mine usually last about 6 months

    You have a new mech every 6 months?!

    Premier Icon b230ftw
    Free Member

    If it’s an early 90’s Deore DX rear mech, then no, they don’t wear out, ever. It’s not possible. 😃😃😂

    Premier Icon thepurist
    Full Member

    2mm allen key, some brake cleaner, some grease. You don’t want drop the little screws and lose them, so don’t try doing it on a gravel driveway or a deck with slots in it:) Video below.

    Also be aware that the 2mm hex screws are easily rounded off by hamfisted people using old tools trying to rush the reassembly in poor light. Allegedly.

    Premier Icon chrishc777
    Free Member

    You have a new mech every 6 months?!

    Well, every 3 on average. I have 2 bikes, although admittedly the trail bike might do 9 months while the big bike will do 4-6

    Premier Icon wildfires3
    Full Member

    My 96 Deore LX is still going strong, thousands of miles through everything on it and it works no issues.

    my 19 Deore on the other had is toast.

    Premier Icon airvent
    Free Member

    Well, every 3 on average. I have 2 bikes, although admittedly the trail bike might do 9 months while the big bike will do 4-6

    You’re doing something very wrong then!

    Premier Icon damascus
    Free Member

    Try a new inner and outer cable first before you replace it.

    Premier Icon Scienceofficer
    Free Member

    I’m bemused someone even asked this question, the answer to which is ‘Duh, yeah!’

    Premier Icon Aidy
    Free Member

    I’m bemused someone even asked this question, the answer to which is ‘Duh, yeah!’

    Well, yes – nearly everything wears out eventually. It’s a question of timescale.

    Pivots and springs in a rear mech will obviously wear over time. The 3 months above is fairly absurd, though. I’d expect to need to replace suspension bearings several times before you got to the natural lifespan of a rear mech.

    Premier Icon chestercopperpot
    Free Member

    Yes they develop slop (Shimano) where the jockey wheel cage is attached to the rest of the derailleur and some of the other pivot points. It can be difficult to feel when the whole thing is under tension! Depends where you ride and how much of beating your mech gets. Mine usually look pretty battered after a few months riding!

    Something that is rarely mentioned is the fact the jockey wheel cage get’s bent/twisted (11sp XT are soft as shite) so the upper and lower jockeys end up out of alignment.

    Most bulletproof setup I’ve had featured a CNC’d cage. It was a lot stiffer than the Shimano one it replaced (got bounced off a lot of rocks round the lakes and peaks) and I got a year out of it with only 2 hanger realignments, 1 cable inner replacement and 2 adjustments for the new cables when stretched.

    Premier Icon chestercopperpot
    Free Member

    With Shimano clutches try to not lose the:

    – The housing seal (grease it)
    – The housing bolts
    – The tiny metal clip thing
    – Tension adjuster port cover (if it has one)

    All have potential to fall on the floor and go missing! Also a tiny bit of loctite on the clutch tension bolt gives it a bit of resistance to undoing. I like a thin coat of moly driveshaft grease (NLGI 2) for the clutch wheel itself!

    Premier Icon footflaps
    Full Member

    I’d change the cable before looking at the rear mech, they can fray at the shifter which causes shifting problems.

    Premier Icon beanieripper
    Free Member

    Jees 6 months for a rear mech! I just sold an XT from 2005ish. Done thousands of miles. eBay buyer was chuffed to bits. I would go with hanger alignment.

    Premier Icon ibnchris
    Full Member

    Not sure I’ve ever had a ‘new’ one and they all seem to work fine. As a couple of folk have said, got some much older ones which do seem to have weathered better. But that could also be because I don’t rode the 9speed bike as much these days. In fact it’s currently in SS mode

    Premier Icon martymac
    Full Member

    My money would be on either cable needing replaced or hanger alignment.
    Mechs can get sloppy of course, but I noticed (while cleaning) that my mech could be moved side to side (a lot) so I checked the hanger bolt, it took 2 full turns to tighten it up.
    Shifting while it was so loose was still absolutely perfect.
    That was on a 2015 xt setup on my Ebike.

    Premier Icon ayjaydoubleyou
    Free Member

    <embarrassed admission>
    It was the b-tension screw. Not correctly set when I changed from a larger cassette to my current one.
    Similarly, chain is a link or two too long hence the dropping.

    Shifting massively improved, will see if the dropping is also fixed or if I will be taking the thing apart to up the clutch tension.

    Will be giving it a decent clean tomorrow too.

    Premier Icon martymac
    Full Member

    Excellent, at least it didn’t cost you a wheel.

    Premier Icon Larry_Lamb
    Free Member

    A new mech every 6 months? 🤣🤣🤣🤣🤣🤣

    Premier Icon irc
    Free Member

    Your spare is just as likely to be bent. A proper tool is one of the best investments you can make.

    My tourer got the hanger properly bent by airport handlers. After a LBS straightened it using the tool(steel frame) it was actually better than it had been before it got bent. Guess it must have been a few degreees out without me noticing.

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