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Bike sounds like coffee grinder!

hootshoots Posts: 134
edited January 2012 in MTB workshop & tech
Been out on my bike this afternoon and noticed that the drivetrain is making a strange noise when under power - sounds a bit like an old coffee grinder.

I'd put the noise down to the chain rubbing on the front mech, but strangely, it still made a noise in middle ring-cog combination. I've been through the 'usual suspects' (with the bike on a workstand) but can't trace the source, just wondered if anyone has any sensible suggestions for the source of the noise?

Here's what I've checked so far:

The chain was cleaned and lubed before the ride, and it's only about 20 to 25% worn.
Gear indexing is spot on and shifts up & down both front and rear are perfect. The chain doesn't rub on the front mech - apart from slight rub on extreme 'cross over' combinations that I don't normally use i.e. big ring to largest rear cog.
Front mech is a direct mount job, and it looks and shifts OK - doen't look like it's been knocked or bent in any way.
Bottom bracket is good, with no detectable play or notchiness.
Rear wheel is sat in drop outs OK and QR is tight.
There is some play in the freehub (it's a Shimano XT wheel - only a few months old) - I can't feel any notchiness and it seems to spin freely, but I'm wondering if this is a potential source of the noise(?)
Finally, FWIW, the drivetrain is a 3x10 SLX/XT mix and is about 10 months old, it's only had light use, as I use my other bike more regularly.

Any sensible suggestions/advice welcome.

TIA

Posts

  • AnonymousAnonymous Posts: 79,692
    Muddy ride?

    Grit in [insert any component here].

    Is the noise coming from the rear wheel area or the crank area? If the rear wheel then quite possibly just grit anywhere in the chain, mech, cassette, brake pad/disc. On the crank end, then grit in chain or in the crank mechanism or BB bearings.

    Did it start making the noise after cleaning and had you jet washed it, especially around bearing areas? (if so, don't!)
  • Andy BAndy B Posts: 8,115
    Checked your pedals?

    Jockey wheels?

    What was the last thing you did to the bike before it started making the noises?
    2385861000_d125abe796_m.jpg
  • hootshoots Posts: 134
    Cheers for the replies & suggestions. Here's some further info in response to deadkenny's post.

    Not a particularly muddy or gritty ride. I'd cleaned the bike after its previous outing, so drivetrain was pretty clean. I lightly oiled the chain with Muc-off wet lube a couple of hours before the ride yesterday - the bike was making the noise as soon as I set off, and didn't seem to get any worse or better during the ride.

    It sounds like the noise is coming from the rear hub/mech area. I've cleaned the jockey wheels, but haven't checked 'em for play yet - I'll check them and the pedals this evening.

    Thanks again for the feedback.
  • hoots wrote:
    I'd cleaned the bike after its previous outing, so drivetrain was pretty clean.

    Jet wash or old school brushes / sponges?
  • bails87bails87 Posts: 13,317
    Is it constant? Only when pedalling? Only when freewheeling?

    Is there any resistance in spinning the wheel?
    MTB/CX

    "As I said last time, it won't happen again."
  • hootshoots Posts: 134
    Bike wash wise, I use warm water, cheapo car shampoo and old brushes & sponge - oh, and as the bike (Zesty) has the deserved reputation as a 'water collector', I pull the seatpost out and turn it upside down to drain the water out.
    (Having seen how quick one of my friends wrecked all the bearings on his FS bike, I steer well clear of jet washes for bike washing)

    The noise is only when pedalling, and gets worse the more effort I put into pedalling i.e. uphill or changing into higher gear to accelerate along the flat. The wheels seem to spin freely when on the workstand, but I have noticed more resistance than usual when back-pedalling the cranks (this seems to have got worse in the last 2 or 3 weeks).
  • benpinnickbenpinnick Posts: 4,148
    What sort of coffee grinder, burr or blade?
    A Flock of Birds
    + some other bikes.
  • AnonymousAnonymous Posts: 79,692
    Burr is good.
  • Ive had the very same thing on my Xt 10sp . Lubed also with Muc off wet before ride . Tried all options to stop the noise and in the end i changed the chain ( chain was only 6 rides old Shimano ) Tried a KMC on and the problems gone . Think the grit must have been well caught in the links as i degrease always .
  • So what you're saying is it's because of an almost new Shimano chain, prob still with factory grease?
  • bails87bails87 Posts: 13,317
    You haven't routed the chain the wrong way on the tab on the rear mech cage have you.....?
    MTB/CX

    "As I said last time, it won't happen again."
  • benpinnickbenpinnick Posts: 4,148
    bails87 wrote:
    You haven't routed the chain the wrong way on the tab on the rear mech cage have you.....?

    Good shout, also check the jockey wheel isnt rubbing the cassette.
    A Flock of Birds
    + some other bikes.
  • That's what I thought - but he says it's under power.... Seems odd to me.
  • AnonymousAnonymous Posts: 79,692
    Under power, i.e. when the chain is moving?

    After washing if I don't do a deep clean on the chain, cassette and mech, I'll get a grinding noise. Seems to be grit and stuff embedded in the chain etc and seems to be worse by giving it a clean without a full degrease. That said, oil, ride it when it sounds gritty and the sound is gone a short while into the ride.
  • benpinnickbenpinnick Posts: 4,148
    deadkenny wrote:
    Under power, i.e. when the chain is moving?

    After washing if I don't do a deep clean on the chain, cassette and mech, I'll get a grinding noise. Seems to be grit and stuff embedded in the chain etc and seems to be worse by giving it a clean without a full degrease. That said, oil, ride it when it sounds gritty and the sound is gone a short while into the ride.

    Yep, that happens to me too. Only in some sprockets though as a rule. You can actually feel it through the cranks too.
    A Flock of Birds
    + some other bikes.
  • So what you're saying is it's because of an almost new Shimano chain, prob still with factory grease?

    No m8 , took the grease off from new :wink:
  • Dan_xzDan_xz Posts: 130
    First thing to do is check the pedals and bottom bracket are tight enough and havent worked loose. There may be enough play that you are flexing it when putting power down and causing the chain to scrape on the front mech. I've seen it a few times - usually when people have greased the axle to stop is seizing.

    Next spin the back wheel and watch the disc rotor stays evenly between the pads. Check the rotor bolts and reset the brake.
    .
    Also check your frame for cracks around the BB and chainstay and check the rear cassette is on tight and that the real whel spins smoothly on it's bearings.

    Those are just some checks to do before spending money randomly replacing components in the hope of hitting the problem (which we all have done at some time!)
  • cooldadcooldad Posts: 32,601
    So what you're saying is it's because of an almost new Shimano chain, prob still with factory grease?

    No m8 , took the grease off from new :wink:
    Why. The lube it comes with is excellent stuff, and penetrates the rollers etc.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • AnonymousAnonymous Posts: 79,692
    Out for a ride today and had the coffee grinder with me. Reason - mud. A hell of a lot of mud!

    Thought my bottom bracket was shot as it just felt notchy pedalling, everything grinding away, but it's purely the thick mud in the chain and cassette (despite the wet lube). At least I hope so. Seemed to go away after a blast along dryer sections and returned going through the bog.
  • I started to get this noise after a few months on my XT 10-sp drive train. I'm sure I've seen someone describe it as being like the noise of a rollercoaster being pulled up a hill on a chain and it is a lot like that, as if the chain is catching on the lip of every tooth.

    Chain wear wasn't anything like enough to warrant replacement but I did anyway (another shimano) and the noise went for a few rides, only to come back again. Chain obviously not the problem, since it was virtually new, also not mud as it would happen at the start of a ride when everything was clean (and I do degrease and lube properly).

    Out riding yesterday I noticed that I only get the noise when in the middle ring and lowest 1 or 2 sprockets, but not when in the granny ring with the same sprockets - so you'd think it was down to the middle ring being worn - but I don't get the noise in the middle ring with higher sprockets! So am confused. But I don't think it's the chain, or dirt, that causes this. Or rubbing on the front mech; I know what that sounds like.
    2011 Canyon XC 8.0 (Monza Race Red)
    1996(?) dyna-tech titanium HT; pace RC-35's; Hope Ti Hubs etc etc
    Bianchi Road Bike
  • Got this last weekend on a brand new bike with XTR 10sp set, but it was REALLY muddy.
    A mate also with a new bike an XTR crank and XT mech setup on the same ride didnt have the same problem.
    Solved it by degreasing everything and cleaning all the muck out of chain and rear mech wheels.
    All sounding good again now.

    The difference between the two bikes....I was using muc-off wet lube and he wasnt.

    From other threads, I feel it maybe the muc-off wet lube attracting and holding on to too much grit or me using too much lube?

    Will try again this weekend having relubed and wiped off excess this time. But if I get the same, I'll try and different lube.
  • hootshoots Posts: 134
    Thanks for all the comments and suggestions re: my OP (apologies for not responding earlier - been out of action with man-flu!). At long last I've finally got 'round to doing a proper deep clean of the drivetrain and doing a bit of investigation - and I think I've found the culprit(s). I think the source of the noise is/was a combination of two things; muck/grit inside the chain (and not sure if it's co-incidence, but I've recently started using Muc-off wet lube), and the rear hub. A really thorough double degrease, scrub and light lube of the chain has silenced the chain - but now I can hear what I guess is potentially more serious, which is the clunking from the rear hub. I think I've narrowed it down to the freehub body (it's an XT hub) - it makes a continuous 'clunk clunk clunk' when pedalling, but stops making the noise when freewheeling. There's no play in the main axle bearings. A friend has said the freehub on her XT wheel failed without warning mid ride a few months ago, so I'm wondering if mine's on its way out(?)
  • Chunkers1980Chunkers1980 Posts: 8,035
    edited December 2011
    clunk clung while engaged, then it's unlikely the feehub.

    So after all that a clean solved it.... ffs
  • 2+2 on the lube doesn't always make 4 - you live in yorks right? Bet there's lots of sandy type trails?
  • hootshoots Posts: 134
    "So after all that a clean solved it.... ffs" haha, well I wasn't expecting that comment....not been in the boozer have we?! ;)

    The chain was doing the dirty chain coffee grinder type racket at the beginning of the ride - and following its previous ride, the bike & chain had been given the same routine post ride clean that I've used for years on my off-road bikes - & I've never had a similar noises at the start of a ride with 7, 8 or 9 speed chains using the same cleaning routine. To silence this noisy 10 speed chain, I had to use an ultrasonic bath to clean it! Looking at what other people have said about the Shimano directional 10 speed chains, I think that's part of the problem - it does seem way more susceptible to mud than 9 speed KMC or SRAM chains. (BTW, the chain is on the right way round) - it still shifts more or less OK, but what a racket! I've another bike running a SRAM 2x10 with SRAM chain, which seems a bit better - so although Shimano recommend only using their own directional chain with Dynasis gears, I might pop the SRAM chain on my SLX equipped 3x10 bike and see how it behaves.

    "2+2 on the lube doesn't always make 4 - you live in yorks right? Bet there's lots of sandy type trails?" Yeah, we're riding in South Pennines/Dark Peak a fair bit, but use local knowledge to stay off worst 'grit & s**t' routes in wet weather ('cos it can get reet expensive in chains/cassettes/chainrings otherwise). I know the score with overlubing chains with wet lube (and I'm too tight to waste the stuff!), so use it quite sparingly and wipe the excess off. For anyone interested, the new Muc-off ceramic lube does seem to pick up and hold less mud than their blue wet lube - the ceramic stuff also doesn't smell like cat p***.

    As far as the hub goes, I can see where you're coming from with freehub - any other ideas? maybe a cracked bearing in the axle race? Any sensible suggestions on the hub clunking would be most welcome. Cheers.
  • hootshoots Posts: 134
    FWIW, I found the source of the 'clunky' graunching noise, it was a knackered bearing in the freehub - never had one go in a Hope hub before (but it has seen a fair bit of use). Anyway, some good quality aftermarket bearings have sorted it:)
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