[mattyuk2002]

OK – warning up front this is a rear derailleur noise question. I’m a pretty good bike  wrench (as the Americans would say) but neither I nor my local bike shop can figure this one out. I’ve searched everywhere and can’t find the same problem online. Don’t seem to be able to search cc forums which is odd but it didn’t throw up anything via Google anyway.

Anyway – I have noise on my rear cassette. All sprockets, but worse in the central few. 105 5700 cassette, shifters, derailleur. Currently new SRAM chain but same with original 105 chain.

It’s coming from the jockey wheels – You the derailleur “kicking” (jolting) several times per revolution. Only way to stop it seems to be to slacken the chain a bit by hand by pulling the derailleur arm down. Just because the noise is the kicking from the derailleur doesn’t necessarily mean the derailleur is at fault though. So far I’ve tried:

– New cassette and original cassette

– New SRAM chain and original 5700 chain (meshed with original cassette)

– Replaced the hanger and had alignment checked at shop

– Double-checked chain length using online calculator.

– New freehub bearings, and when that didn’t work, new wheels

– Checked frame straight (carbon, but checked anyway)

– Full strip and lube of jockey wheels which are in excellent order

– Put on a spare very-little-used Dura Ace rear derailleur. Same problem.

– Messing with the B-screw – doesn’t actually seem to do anything at all.

All I can think is to try a new shimano chain, but I feel like I’m pouring money down the sink at the moment and getting nowhere. Any suggestions on what else to check?

Topic

[mattyuk2002]

I think I might just keep it

I think I might just keep it to look at rather than riding it and having to go through all that again.

[mattyuk2002]

Thanks Guts – no amount of

Thanks Guts – no amount of adjustment with the barrel when in a single gear would quieten the noise, so I just couldn’t see it being the shifter anyway. It does seem to have been somethign with the spacer/cassette as you intimate.

[HoarseMann]

Could be that the cassette

Could be that the cassette looked and felt tight, but it wasn’t quite enough without the spacer. Fingers crossed you’ll be gliding along in blissful silence on the next ride 🙂

[mattyuk2002]

Thanks HoarseMann. I take

Thanks HoarseMann. I take your point and agree for actual riding, but to be honest I still don’t really see why I was getting all this noise due to a “missing” 1mm spacer, noting the noise was coming when the bike was on the stand not under power.

Why has the cassette 1mm sideways made a difference? As the derailleur is adjustable, all that has really changed is the chainline, but only a tiiiiny amount.

I suspect I’ve changed something else in truth without realising eg. lock ring torque/wheel alignment in dropouts or similar, and that is what has made the difference. Like I said the bike shop couldn’t put their finger on an actual cause either, although credit to them, they did ask if I had the 1mm spacer on me, which I didn’t at the time.

[HoarseMann]

Glad it’s sorted. I’d be

Glad it’s sorted. I’d be tempted to source a slightly thicker spacer and make sure that there is zero play in the cassette and no clunking sound when first putting the power down. That lock ring needs quite a bit of force to tighten down properly and compress the cassette cogs into a solid block.

[mattyuk2002]

Yes but you’ll have to

Yes but you’ll have to collect it from 2m away and we have to be doing exercise at the time.

There was no difference in actual movement of the cassette on the freehub before vs after the additional spacer. At least not that I could tell. Could there have been movement between sprockets perhaps? Not that I can see how that would cause the noise I was seeing. Eugh…

Anyway I’m going to try not to breathe on the cassette for a few days and hopefully the fix will stick.

[Drinfinity]

Tiny spacer – can I claim my

Tiny spacer – can I claim my mince pie? The lockring won’t lock the cassette on firmly if spacers are missing, as it will bottom out on the freehub body instead of fully loading onto the cassette. 

[mattyuk2002]

OK, so I’m going to say this

OK, so I’m going to say this quietly in case the gods are listening, but it seems to be fixed. All I did was take off the crankset and put it back on, so it’s possible I’d over-tightened (or maybe under-tightened, but less likely) the hollowtech II preload cap.

I’m praying that’s it, but can anyone explain to me how in the **** over-tightening the bottom bracket would cause that sort of noise and rear derailleur kick in the cassette? I don’t see any logical link at all.

I can’t think of anything else I did differently this time apart from…oh no hang on, I forgot – I put one more tiiiny half-spacer on the rear cassette. I sure I read somewhere about the aksiums needing some weird 2mm spacer or something so maybe that’s what’s made the difference. That would make more sense, but I’d already tried that combination of spacers before and it made no difference. There is also still the same amount of “play” ie. tiny rocking on the cassette as before the extra spacer went on.

Best guess, combination of the shop straightening the hanger and the extra tiiiny spacer is what has made the difference.

Any final thoughts welcome but if it stays fixed, thanks to everyone for your help. We appear to be there. It’s still not the quietest drivechain I’ve owned, but it’s within the “normal” range I’d say.

 

[Guts76]

To take the shifter out of

To take the shifter out of the equation, use your hand on the cable to shift the rear derailleur up the cassette to see if you can set it into a good path. Also it sounds more like a cassette/hub issue then a drivetrain issue. I would try a 10 speed shimano hub wheel that doesn’t introduce and play into the cassette…

[Grahamd]

Dingaling wrote:

What has the rear derailleur got to do with pull ratios? A derailleur moves freely between two extremes and the shifter does the indexing. As long as the indexing matches the spacing of the sprockets the derailleur will work. 

I am no expert, so perhaps I should have said they have differing indexes. I can categorically state that new new Tiagra RD does not work with old 105 levers. You can reach limits of cassette but does not settle mid range, very similar to the video. 
 

So anyone needs above RD message me.

[Nick T]

You assume derailers all

You assume derailers all pivot on their axes an equal distance to each other for a given amount of cable pulled through them. 
Shimano 10 speed and earlier had a cable pull of 2.4mm or more, and derailer ratio of 1.7mm for every 1mm pulled – 11 speed has a pull of 2.7mm and a ratio of 1.4mm

[mattyuk2002]

Thanks Jimmy – whilst on this

Thanks Jimmy – whilst on this journey I did notice I had reinstalled the tension jockey wheel backwards. Was delighted that I might have found the cause until I reversed it and…no change. I’m pretty sure the guide pulley is non-directional? Plus I tried with a different (short cage) derailleur and got the same sound.

I’ll have another stare at it in slow mo and see if I can see anything new with your suggestions in mind.

[Dingaling]

What has the rear derailleur

What has the rear derailleur got to do with pull ratios? A derailleur moves freely between two extremes and the shifter does the indexing. As long as the indexing matches the spacing of the sprockets the derailleur will work. 

[mattyuk2002]

Thanks Grahmd. yep. 105 5700

Thanks Grahmd. yep. 105 5700 – matches the cassette, chain, front derailleur and crankset, all 5700

[Jimmy Ray Will]

OK, very interesting. 

OK, very interesting. 

Chainstays a re short, but not ridiculous… the shorter the stay, the more volatile the gearing as there is less chain to absorb any alignment / chain line issues. 

The chain ring question was aligned to the above… all about the distance / angle of chain to the rear mech. 

A couple of things I’d suggest checking. First, are your jockey wheels in the right way around? I ask as they are directional.

I’d also hazard a bet that if you changed to a long cage mech, the problem would go away.

The video does not show anything obvious. Have you been able to identify where the skipping is happening? This is what I’d focus on for now. 

Is it skipping on the bottom jockey wheel, or on the cassette, or indeed on the chainring? 

[Author]

Replies