Mystery Creaking + Rear Mech Issues

Dezza

Sorry for another one of these threads but i'm pretty much out of ideas.

I get a creaking like noise which sounds like fast tapping on a metal surface, usually riding under load while out of the saddle.

Over the last month or so ive tried the following:

* Removed, cleaned and relubed Hollowtech BB (twice).
* Removed, cleaned and relubed pedals on crank. Inserted new grease into speedplays.
* Regreased speedplay cleats (weekly).
* Replaced chain and rear cassette.
* Greased dropout and checked bolts.
* Greased skewers.
* Replaced rusty lower headset bearing unit and regreased.
* Greased handlebar/headtube/fork spaces.
* Tightened front mech clamp.
* Experimented with different seatpost/saddles.

Noise is still there.

My next plan is to check the bottle cage bolts... but ive ridden without a bottle in before and still heard the noise so i doubt its this.

One thing I have noticed is my rear mech seems very stiff. If I pull down the mech on an other bike it springs back in a sprightly fashion, but this one is laboured and stiff. If i jiggle it a bit I can hear a squeak but it sound different to the one I am hunting. I've tried to work oil into the two main pivots which has helped a bit, but it still doesn't *spring* back. Is there a way to improve this? Could this be effected by chain length as I recently swapped from a 25 to 28 sprocket. I calculated it using an online tool but I may have ballsed it up?

Thanks.

farrina

Only a thought but have you tried removing the chainrings and greasing them where they mate with the chainring spider. I had a noise that drove me mad for months with a Shimano DA and this sorted it.

I assume you have inspected your frame for any cracks (although in fairness if its got as far as a creaking crack you are likely to feel the movement)

Good luck

Alan

Dezza

farrina wrote:

Only a thought but have you tried removing the chainrings and greasing them where they mate with the chainring spider. I had a noise that drove me mad for months with a Shimano DA and this sorted it.

I assume you have inspected your frame for any cracks (although in fairness if its got as far as a creaking crack you are likely to feel the movement)

Good luck

Alan

Thanks Alan.

Hmm.. not thought of that. I did check the hex bolts and they were tight (Ultegra Chainrings) so i left alone. I'll have a go at removing and greasing.

I'm a bit OCD about keeping the frame clean and ive not seen any cracks so far. I'll give it a once over tonight. Is there a common place where carbon frames fail?

Dezza

I think I've cracked it. It looks like the noise was from the rear mech.... The tension of the chain when pedalling out of the saddle was straining the stiff pivot joints, causing a right racket.

I've managed to work some oil into the pivots but they are still a little stiff. Does anyone have a suggestion on how to make the action nice and smooth again?

onbike 1939

Dezza wrote:

I think I've cracked it. It looks like the noise was from the rear mech.... The tension of the chain when pedalling out of the saddle was straining the stiff pivot joints, causing a right racket.

I've managed to work some oil into the pivots but they are still a little stiff. Does anyone have a suggestion on how to make the action nice and smooth again?

It does seem that the stiff pivots were responsible for the return spring on the Rd not working properly. If the pivots are stiff due to winter crud it my help to put the chain on the smallest cog and then pull the gear cable away from the frame causing the RD to move over its entire range. Do this repeatedly while using GT 85 on the mech until you can see some improvement. If this fails then disassembling of the RD or replacement would be the answer I would imagine.

Dezza

I'll give this a go. Thanks

dee4life2005

I had a stiff rear derailleur (ultegra) not that long ago, to the point where you moved the mech by hand and it wouldn't spring back at all - or very little. I only noticed as I had a thick black oily line over the chainstay as the RD was no longer taking up the slack in the chain properly - oops.

I ended up taking it off the bike and giving it a proper de-greasing whilst working the movements by hand to get all the crud out. It was manky. Once de-greased and rinsed / dried I give it a bit of light oil on all the pivot points, re-installed it, and it's been like new ever since.

Have had to do similar with the brakes as well, as they go a bit sticky after a while too.

Dezza

dee4life2005 wrote:

I had a stiff rear derailleur (ultegra) not that long ago, to the point where you moved the mech by hand and it wouldn't spring back at all - or very little. I only noticed as I had a thick black oily line over the chainstay as the RD was no longer taking up the slack in the chain properly - oops.

My RD is also ultegra and you've just described my situation perfectly. I did wonder why the hell I was getting a oil stripe like that!

dee4life2005

The black stripe was what made me look at the rear derailleur ... I thought there was something seriously wrong with the bike at that time as it was sounding like a bag of spanners. It was all related to the RD not taking up the slack properly, so the slightest bump in the road and the chain was hitting the chainstay and same when freewheeeling.

Kind of my own fault really as up until that point I don't think I'd ever cleaned the RD, just a bit of lube on the pivots. I think it was trying to tell to clean it ;-)

Hope you get as good results after giving it a clean.

Dezza

I followed your advice and gave it a damn hard degreasing, wash then light oil and it seems much better now. It's not as loose as my missus's tiagra mech when i compare it, but at least its smoother and squeak free.

I'll mark this one down to experience me thinks.

Thanks all for your help.