Noise coming from rear hub/derailleur
 

I gave my bike a really good clean for the first time in ages at the start of the week, and decided to take my chain and rear derailleur off so I could get in all the nooks and crannys and soak my chain in some degreaser.

Now that I've put it all back together I'm getting a soft clicking noise from the rear of the bike. It happens when I backpedal, pedal normally or roll backwards, but not when I coast forwards so I assume it is something to do with the rear derailleur rather than the hub. When I took it off though I simply unscrewed the main bolt and screwed it back on afterwards.

Have I put it back on wrong? Is it normal for a derailleur to need readjusting after such a simple thing? I also used a fair amount of quite potent degreaser on it and haven't put and lube back in the system yet but it sounds worse than just dryness. What should I be looking for to make sure the derailleur has been put back on in the right way?

Not sure if it makes any difference but for the record it's a 9-speed Deore LX derailleur.

Thanks.

Make certain your chain is routed through the derailleur properly, not over the tab on the jockey wheel cage.

Is that the tab between the two sides of the arm going to the bottom wheel? It doesn't seem to be contacting it at all so I think I have it in the right place. The chain runs to the rear of that tab.

Your problem is almost impossible to assess without either more details/info or the bike in front of us. cor suggested the first step, sort of, making sure all was reassembled correctly. Yes, modern index systems are very sensitive to minor adjustment differences. Cleaning parts, chains particularly, can result in noises from wear being greater as the sound damping qualities of sludge/grime are now gone. But this louder state also allows one to fine tune index coordination, der throws (limit screws) and hanger alignment with greater feed back. I always add lube after all adjustments for this reason.

I won't tell you how to insure whether the system is reassembled correctly. That's for on line tutorials or a visit to your LBS. There are far too many points of detail for this medium. Andy.

Like I say, all I did was unscrew it from the hanger and screw it back on.

Would you say it sounds like a derailleur aliment problem instead of anything else then?

Thanks

As Andy said, it could be a number of things. It could be that the dirt and gunk were insulating the noise, and cleaning things exposed another issue. I would put the bike on a workstand and examine the chain, derailleur, and cable carefully.

I agree it could just be a side effect of a clean chain, especially if you have not lubed it yet or are using a very light lubricant - could easily be chain/pulley interface. A mechanic would put the bike on a stand, pedal the bike and look and listen at the rear area of the drive train. You can do the same. If you have another bike that's quiet you could do so with it and compare. If you still can't figure it out then get to a bike shop, co-op or knowledgeable friend.

I've had a bit more of a play and it seems to ride pretty smooth in the inner front and second to largest cog. If I stick it in the largest cog it looks like it's trying to skip from side to side. The smaller end of the cassette is nosier but without such an obvious movement.

I've been trying to work through the park pools site on derailleur adjustment but it's my first time doing anything like this and I'm getting a bit lost.

How tight is your cassette lockring - if the cassette looks like it's wobbling significantly (and it would be most apparent on the largest cog, I would have thought), maybe it's not cinched down as tight as it should be (and the recommended torque levels for cassette lockrings is suprisingly high AFAICR.)

edit - Depending on what 'it' is (wobbling), maybe also check your chainring bolts for tightness.

The cassette looks pretty solid. It's sort of the chain snaking a tiny bit as it goes in. There's also now a slightly disconcerting knocking noise when I'm turning the crank. I think I'm gonna have to take it into an LBS =( .

Well this morning I took it all off and put it back on again and have been fiddling and thought it was still pretty noisy. Went to cycle to the LBS and on a smooth section of path suddenly realised how quiet it is. The problem now seems to be contained to a bit of trouble shifting to an easier gear at the small end of the cassette. Does that narrow down what the problem might be?

Tightening the RD cable a tad, maybe? *shrugs*

No, because if you mean the smaller cogs that's usually considered harder pedaling - more pedal pressure for a given speed. Shifting to the small cogs is done entirely by spring tension of the derailleur pulling on the cable, so friction in the cable/housing would make those shifts slower.

I mean that shifting up from the very outside of the cassette, for instance going from the 12T to 13T (or whatever it is on my cassette). It isn't as smooth as it should be and sometimes doesn't shift. If I shift it up another gear then drop it back down it seems to sit there quite smoothly though.

Comparing something to what it "should be" is less helpful than comparing it to previous performance. If the problem did not occur previously then something you did during the cleaning process was the culprit. If it's OK shifting in one direction but not the other it is unlikely to be a simple adjustment problem. It could be that a housing end is not properly seated but not possible to tell long distance.

I'll add one more aspect. As the grime and grit is washed out of chains the links' side to side flexibility increases slightly. So the , by novice mechanics, assumption that a clean chain will shift faster (ALL other things being equal) is often wrong. Andy.

Sorry, I assumed it used to perform as it should (quickly changing gear). Now it takes a good 10 seconds of bumping on to the next cog but not quite making it. I don't think this can but put down to the chain being more flexible.

Upon removing it all I did was unscrew it from the rear hanger. I simply screwed it back on when I put it back. Changed absolutely nothing else.

Greetings Dheorl,

You’ve stated that you only unscrewed the rear derailleur however; it seems somewhat pointless to have removed the rear derailleur without having disconnected its shifter cable. Did you also disconnect its shifter cable?

If you didn’t disconnect the rear derailleur’s shifter cable and simply allowed the rear derailleur to hang from its shifter cable, the last segment of its cable housing (at either end) may not be fully seated in their stays on the bike’s frame (potentially attributable to grim within the stays) and/or the last segment of cable housing may not be routed precisely in the same manner as it was prior to the derailleur’s removal, in which case, it can cause the problem that you’re experiencing.

When I read about issues of this nature, it makes me want to take a ride to the OP’s location to resolve the issue (and I have at times when they’re located in my vicinity).

I still can't help thinking that your symptoms as you describe them sound very much that they could be solved with a slight tightening of your RD cable (that it's not smoothly shifting *up* the rear cogs, but it's dropping down to the smaller ones just fine).

What Gnosis, who posted this helpful answer as I was typing the above, said could cause the need for a possible cable-adjustment.

You asked for assistance but now you are offering your opinion of the expert advice you are receiving - based on what? When a chain is worn it often develops more side play. When cleaned that side play may show up, which means the chain has to be pushed further to accomplish a shift, particularly when shifting to a larger cog or chainwheel. One can get some idea of the amount of side play by pushing the top run of the chain toward the wheel in the area between chainwheel and rear cog, with the chain on the outermost position.

As both Gnosis and I noted it's important to make sure housing is seated, and you did not respond to that point when I brought it up. You also started off with a noise complaint without having lubed anything. I think you would be best served by getting in-person assistance, as both Andrew and I suggested earlier. A quick perusal of some of your previous posts did not indicate where you live and you don't list your location, so no way to tell what resources you have available.

This forum is a two-way street - it's helpful for the person needing assistance to both take some responsibility and to respect the advice given, at least to the point of asking for clarification before dismissing what is offered.

Thanks for the calm sensible reply. I removed it partly so I could lie the bike down wheelless on the drive side without worrying of damaging it (it's a long cage so sticks out a fair way) and just so I could get it at a better angle to clean the derailleur itself. The cable housing all seems to be in the correct places. I did wonder if the routing might have changed slightly but I can't see how else it could have gone before. If this is the case what is the best fix that I can try?

Based on the fact that it's been clean and working fine not that long before.

I know what types of sounds an unlubed chain is likely to produce and this is not at all similar. I did go to get in person assistance but as mentioned the mechanic at the LBS was not in and upon riding around it actually seemed slightly better than it was before.

I understand this forum is a two way street but I was getting such a feeling of aggression from your replies that I feel I quite understandably became a bit defensive.

Garbage in, garbage out. "I gave my bike a really good clean for the first time in ages" does not tell us that "it's" been clean before," but rather that the chain was likely full of gunk. If you felt aggression at all previous to my last post (which in fact was not aggressive but rather confrontational) then it was neither in my words nor in my intent.

The chain was full of gunk, but commuting does that quite quickly. First time in ages by bike cleaning standards to me is anything over a couple of weeks. Maybe that's what happens when you have a mtb background. Sorry if I was not specific enough at the start.

Now that we've got that cleared up and know there was no ill intent from either side do you have any further suggestions? Seems like the cable routing might be likely as that's the only thing I can see will have changed between taking it off the first time and the second time. Should I take it off and try and figure out the original routing again or is there a way to easily compensate for it as is?

Also, I digress, but isn't confrontational just dealing with something aggressively?

It's not a matter of routing the housing but rather that the housing is properly seated in the ends and that the ends are properly seated in the stops. Frankly, though I mentioned seating as a matter of course to eliminate another variable it's not likely the cause of poor shift to a larger cog but not back down. The chain side-play has not been ruled out, still the most likely culprit in my opinion. I often found drive train problems surfaced after a chain cleaning or a drive train overhaul on a customer's bike.

As to the digression, my parsing of the two terms comes from my time in a crisis counseling center. Confrontation is firm setting of a limit and a request for change, whereas aggression is forcing of one's views (or body of course) on another. There's nothing wrong with confrontation done responsibly - it assumes the other person is strong enough to hear a frank appraisal and has both the ability to change, as the right not to do so (though that may have consequences). Aggression denies the rights of another person.