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lordofthemark
11-06-2017, 08:39 AM
As many of you may be aware the squeaking is back, despite the new chain and cassette, and after I lubed the chain (prior to GPR) Jeanne Streetsmarts said something about it sounding like the noise a cat makes sometimes? It is only when I am certain gears, not all. Given that last time Phoenix addressed it by adjusting the derailleur, and that it sounds to me at least like its coming from there, I think it must be the derailleur.

My questions to the hive mind - is adjusting a derailleur hard (assume I have a pretty full slate of tools, thanks to the building's bike room) ? Is there anything I can seriously mess up if I do it wrong?

bentbike33
11-06-2017, 08:48 AM
As many of you may be aware the squeaking is back, despite the new chain and cassette, and after I lubed the chain (prior to GPR) Jeanne Streetsmarts said something about it sounding like the noise a cat makes sometimes? It is only when I am certain gears, not all. Given that last time Phoenix addressed it by adjusting the derailleur, and that it sounds to me at least like its coming from there, I think it must be the derailleur.

My questions to the hive mind - is adjusting a derailleur hard (assume I have a pretty full slate of tools, thanks to the building's bike room) ? Is there anything I can seriously mess up if I do it wrong?

I cannot think of anything to adjust on a rear derailleur that would relieve a squeak. Assuming the squeak happens while pedalling, it is probably one of the jockey wheels that could use some lubrication.

hozn
11-06-2017, 08:51 AM
Adjusting a rear derailleur is easy; you just need a phillips-head screwdriver (or small hex on some newer derailleurs). There are many youtube videos.

But I don't think that's your problem. A misadjusted derailleur won't shift correctly or will make nasty chain grinding noises while it tries to "half shift". Mine is making that noise right now because I probably got a bunch of mud jammed up in there at Iron Cross race.

It might be your jockey wheels on the RD that are squeaking, in which case you can spray them with triflow lube or something and see if that fixes it.

But there are other things that can squeak too: shoes (rubber tread on the pedals), maybe pedals themselves, hub endcaps, etc. But hopefully lubing the jockey wheels is all it is.

hozn
11-06-2017, 08:53 AM
This is probably worth posting. It is the definitive anthology of investigation avenues for squeaks, clicks, rattles, etc.

https://www.sheldonbrown.com/creaks.html

Here's another: http://www.jimlangley.net/wrench/keepitquiet.html

TwoWheelsDC
11-06-2017, 09:02 AM
Can't say I've ever had a "squeaking" that was solved by a simple RD adjustment. If the bike shifts fine (meaning it runs smooth while in a given gear, in addition to actually shifting smoothly) and is all lubed up well, then I can't really think of any adjustment that would fix some sort of nondescript squeaking. If your RD is in need of adjustment, you should be getting some feedback through the drivetrain as you ride, along with some roughness in the drivetrain sound (but not a squeak). Does it just sound like it's coming from the RD while you're on the bike, or have you put it on a stand and traced the sound to the RD area?

One easy culprit to check...make sure your rear skewer is snug. I had a squeak that I eventually tracked down to my hubs, where the little grippers had worn down allowing the hub to move against the dropout, which necessitated keeping the skewers really tight. You generally don't need the skewers super tight, but they should be nice and snug.

Tania
11-06-2017, 09:04 AM
But there are other things that can squeak too: shoes (rubber tread on the pedals), maybe pedals themselves, hub endcaps, etc. But hopefully lubing the jockey wheels is all it is.

Disc brakes too - I've been plagued by this for months now. It's not the standard "tsing tsing tsing" rotor rub, it's more a squeee squeee squeeee. I can prove it's the brakes by loosening up the thru axle just a bit and turning the wheel. We're pretty sure it's frame flex because it only happens when I'm putting down power (and mostly as my left leg starts the down stroke) but not 100%.

I lent it to someone for DCCX and it came back squeak free. For now.

lordofthemark
11-06-2017, 09:08 AM
Can't say I've ever had a "squeaking" that was solved by a simple RD adjustment. If the bike shifts fine (meaning it runs smooth while in a given gear, in addition to actually shifting smoothly) and is all lubed up well, then I can't really think of any adjustment that would fix some sort of nondescript squeaking. If your RD is in need of adjustment, you should be getting some feedback through the drivetrain as you ride, along with some roughness in the drivetrain sound (but not a squeak). Does it just sound like it's coming from the RD while you're on the bike, or have you put it on a stand and traced the sound to the RD area?

I did put it up on a stand and it sounded like it came from there, but I didn't try listening to the pedals, I suppose. Note, I ride regular shoes on the flat side of my dual pedals, and I do not have disk brakes, so its not either of those. Will try lubing the jockey wheels.

hozn
11-06-2017, 09:16 AM
Disc brakes too - I've been plagued by this for months now. It's not the standard "tsing tsing tsing" rotor rub, it's more a squeee squeee squeeee. I can prove it's the brakes by loosening up the thru axle just a bit and turning the wheel. We're pretty sure it's frame flex because it only happens when I'm putting down power (and mostly as my left leg starts the down stroke) but not 100%.

I lent it to someone for DCCX and it came back squeak free. For now.

Is it the front wheel? Just as another thing to throw out, my 15m endcaps for my Novatec hubs squeak a bit; it is solved by adding some grease around the rubber gasket on the endcaps, but has to be re-applied periodically . Not sure what it is about that design, but this is the second hub, so it's something in the design.

But certainly your suspicion that it's rotor rub in certain frame-flex situations sounds likely too, especially if the pads track pretty close. I've definitely had some squeaking when swapping wheels and rotors were no longer correctly aligned. I think the squeak was because I was also down close to the end of the pad and the pad spring clip was starting to rub the rotor. (I've also had it happen where that spring clip gets bent and sticks out in front of the pad, making squeaking sounds, though that usually makes noise when braking too.)

I had to stop and change my rear brake pads this AM on the way into work. They sounded horrible. I think I see why ... :-) Iron Cross was not too gentle.
https://uploads.tapatalk-cdn.com/20171106/1364267c6acfd8fd1b49199ecf050b5b.jpg

Steve O
11-06-2017, 03:07 PM
If you can put it on a stand (or hang it on a tree branch or whatever) and turn the pedals, you should be able to ascertain if the squeak is coming from the derailleur.
If it doesn't squeak on the stand but it does while you are riding, then it is you that is squeaking. :)

Judd
11-06-2017, 03:27 PM
If you can put it on a stand (or hang it on a tree branch or whatever) and turn the pedals, you should be able to ascertain if the squeak is coming from the derailleur.
If it doesn't squeak on the stand but it does while you are riding, then it is you that is squeaking. :)

Don't hang your bike from a tree, Jeanne.

lordofthemark
11-06-2017, 03:47 PM
If you can put it on a stand (or hang it on a tree branch or whatever) and turn the pedals, you should be able to ascertain if the squeak is coming from the derailleur.
If it doesn't squeak on the stand but it does while you are riding, then it is you that is squeaking. :)

http://bikearlingtonforum.com/showthread.php?9501-I-am-delighted&p=127114#post127114

So, er, like yeah.

drevil
11-06-2017, 03:48 PM
...
My questions to the hive mind - is adjusting a derailleur hard (assume I have a pretty full slate of tools, thanks to the building's bike room) ? Is there anything I can seriously mess up if I do it wrong?

There is one thing I can think of where you can seriously mess things up with a derailleur adjustment: if you let out one of the limit screws too much, you could possibly "overshift", which is more likely to happen when going to easier gears/larger cogs. What will happen is the chain will jump over the top of the cassette and get jammed between the spokes and cassette. I've seen it so bad that the person had to break their chain and remove their cassette to untangle the mess. On the other end of the cassette, when shifting down all the way to the smallest cog/hardest gear, the chain can possibly get stuck between the cassette and frame.

I agree with the others that say it could be a jockey wheel squeaking, or like Hozn suggested, a rubber endcap -- which on Shimano hubs I've worked on, the endcap stays stationary while the hub body rotates, rubbing each other and possibly making noise. Check out my pic...

15690

Judd
11-06-2017, 04:30 PM
Don't hang your bike from a tree, Jeanne.

But I will agree that putting your bike in a stand or something else that is not a tree is helpful for locating sounds. I had a squeak once that I swore was coming from the chain ring while I was riding but was actually the squeak of an improperly torqued handlebar.

Steve O
11-06-2017, 10:23 PM
I spent an entire commute once trying to locate a squeak. It was not coincident with wheel rotation, chain rotation or crank rotation. It squeaked when I went over bumps. As I was riding I kept holding different things: fender, bottle cage, light mount, etc. to see if it would stop. But no, every bump, a little squeak.
It had rained the day before, and I thought maybe it had something to do with that. "Dang...it's somewhere here towards the front of the bike." I just couldn't pinpoint it, though. For 20 minutes I searched and searched.
Turns out it was the rain. The rain had soaked the spongy things inside my helmet. Each time I hit a bump the helmet would move slightly and they would rub against the inside of the helmet, making a little squeak. It was so close to my ear that I could not determine where it was coming from. I had a good laugh at myself.

lordofthemark
11-13-2017, 08:54 AM
I put the bike up on the rack, and yeah, I guess this time it did seem like the squeak was coming from the jockey wheels. I lubed them as best I could (I don't yet have spray lube). They still squeak - it looks like the chain presses against the metal thing that holds the jockey wheel. I will get spray lube and try that, but I fear that will not solve it, and again, I am reluctant to mess with the jockey wheel or it's holder. And I fear the rubbing, aside from being embarrassing, is doing damage to the chain.

bentbike33
11-13-2017, 10:24 AM
I put the bike up on the rack, and yeah, I guess this time it did seem like the squeak was coming from the jockey wheels. I lubed them as best I could (I don't yet have spray lube). They still squeak - it looks like the chain presses against the metal thing that holds the jockey wheel. I will get spray lube and try that, but I fear that will not solve it, and again, I am reluctant to mess with the jockey wheel or it's holder. And I fear the rubbing, aside from being embarrassing, is doing damage to the chain.

How many miles are on the derailleur? Sounds like maybe one of the jockey wheels is shot if the chain is rubbing on the derailleur cage (which, by the way, will suffer far more damage from this condition than the chain).

lordofthemark
11-28-2017, 03:16 PM
Well I have ordered spray lube from the evil folks in Seattle (not tim and bobco) .

But I have a different problem. Sunday before last I took my first ride with bar mitts. I always get a little confounded shifting under them till I am used to it, and made the mistake of taking the Custis Westbound, and shifting the crankset into the small gear. Which resulted in the chain getting caught in between the bike and the crankset, so that the bike was immobilized, not even walkable. Not wanting to carry it to a bike shop or a bus, I played with it awhile, and finally brute forced the chain out. Yay!. But after that I found it slipped badly in several gears on the cassette (its okay on the biggest gear, and the four smallest, but almost unrideable on the gears between, which I do like to use). I talked to LSG about this at the next CCCC, and he diagnosed the problem as a stiff chain link which would account for why the slippage was happening right after the chain incident. And he suggested that it would be consistent with the other gears working, if the geometry was such that the chain could fit more comfortably over them. He also gave me a way to check for a bad link.

However by the time I put the bike on a stand and checked, I had forgotten his suggested way to check. I ran the chain around and looked for a particular inflexible link, but didn't find any. I also tried a method I found online, looking for ones that jumped over the jockey wheel when the chain is moved backward, and didn't see any of that either.

Meanwhile I have been riding minus some gear options, which is unpleasant in a couple of ways. Before I take it into a shop, if anyone can either offer an alternative diagnosis, or a way to check for stiff links, I would be happy.

hozn
11-28-2017, 03:23 PM
It sounds like the strategies you used are the same I would use (you can see a stiff link jump over the jockey wheels).

Is it possible you bent your derailleur hanger when you had this chain suck issue?

bentbike33
11-28-2017, 03:41 PM
Given the chain-suck incident and its violent resolution, I would suspect one or more links may be bent, and with that comes the danger of breaking the chain as a plate comes off the pin. This would explain the chain skipping in the larger cogs, but not the largest cog, as the bent link catches on the shifting ramps on these cogs.

Probably time for a new chain. :(

lordofthemark
11-29-2017, 09:55 AM
Here are three pictures of the rear derailleur, from different angles. It does not appear out of place to me, but perhaps others have more insight.
15788

15789

15790

I again looked at the chain. I saw nothing that looked to me like a bad link, no loose plates, and it moved smoothly over the jockey wheel. It did make slipping noises over the cassette gear, but I could not what physically was doing that.

I am thinking of just taking it in to a bike shop at this point. There is one a block from here, and I am sorely tempted.

bentbike33
11-29-2017, 10:01 AM
Here are three pictures of the rear derailleur, from different angles. It does not appear out of place to me, but perhaps others have more insight.

15785

15786

15787

I again looked at the chain. I saw nothing that looked to me like a bad link, no loose plates, and it moved smoothly over the jockey wheel. It did make slipping noises over the cassette gear, but I could not what physically was doing that.

I am thinking of just taking it in to a bike shop at this point. There is one a block from here, and I am sorely tempted.

When you say "slipping noises" do you mean it sounds like it is trying to shift unsuccessfully? Or does the chain pop up to a bigger cog then back down in short bursts? If that, you might just need a slight cable adjustment (probably tightening) by turning one of the barrel adjusters (at the shifter or derailleur) counter-clockwise (lefty-loosey).

hozn
11-29-2017, 10:09 AM
Here are three pictures of the rear derailleur, from different angles.

Probably the most useful angle, when trying to diagnose shifting issue, is one taken from directly behind the derailleur at various points in the cassette; this should show the RD jockey wheel relative to the cogs and indicate if derailleur needs adjustment. Showing this position for a few different cogs (e.g. gears 2, 5, 9) should also hint at whether the hanger might be bent -- though that might also be possible to tell from the angle of the RD cage.

bentbike33
11-29-2017, 10:19 AM
One more thing to check is for a slightly frayed derailleur cable. One or two of the component wires in the cable can break and bunch up in the cable housing leading to all kinds of misbehavior in an indexed shifting system. Your pictures aren't quite high-res enough to tell, but it does not look like there is any fraying near the derailleur anyway.

Judd
11-29-2017, 10:45 AM
I am thinking of just taking it in to a bike shop at this point. There is one a block from here, and I am sorely tempted.

Looks like Karen gave you a lemon. I advise consulting legal counsel at this point. Or just taking it to a cool bike shop that will show you what was wrong and how they fixed it.

lordofthemark
11-29-2017, 10:56 AM
Looks like Karen gave you a lemon. I advise consulting legal counsel at this point. Or just taking it to a cool bike shop that will show you what was wrong and how they fixed it.

I take full responsibility for being a wimp on what some people consider to not even be hills (and thereby causing what was certainly an avoidable chain suck scenario)

Steve O
11-29-2017, 12:31 PM
I'm 50/50 that all you need is an adjustment. A couple tweaks of the barrel adjuster; making sure the limit screws are set right; good to go.

Let me know if that's all it turns out to be.

huskerdont
11-30-2017, 07:29 AM
If you haven't done it much, derailleur adjustment really is the kind of thing where it helps to watch an expert do it once, either in person or on a video. Once you have (and can remember which way to turn the barrel), that part is pretty easy, and if it doesn't work, then you know you probably have something else going on.

lordofthemark
11-30-2017, 08:27 AM
If you haven't done it much, derailleur adjustment really is the kind of thing where it helps to watch an expert do it once, either in person or on a video. Once you have (and can remember which way to turn the barrel), that part is pretty easy, and if it doesn't work, then you know you probably have something else going on.


It is done. Took it to Conte's Navy Yard, they adjusted the derailleur, and that fixed it. They did talk me through it, but wanted me on the other side of the counter while I watched, I probably could not do that myself without watching some videos. The shifting is now fine. They also spray lubed the jockey wheel (my spray lube from Amazon should arrive today along with some new lights, but oh well) and the squeak is gone too.

Steve O
11-30-2017, 11:53 AM
I'm 50/50 that all you need is an adjustment. A couple tweaks of the barrel adjuster; making sure the limit screws are set right; good to go.

Let me know if that's all it turns out to be.


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