Clunking sound from rear of bike - any ideas?

enkoda

enkoda

enkoda

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3 Mar 2010
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Hants, UK
I'm having a bit of an issue as per the title.

If I'm on either of the two largest chainrings at the front and shift from gear 3 into 4 (and all subsequent gears from thereon) a repetitive clunking sound will sometimes start, matching the rotation of the pedals. I just can't pin down exactly where it's coming from but so far here's what I've done:

1 - new chain, new rear derailleur cassette, new pedals
2 - bottom bracket checked
3 - rear wheel bearings checked

Is there anything else I can check before I bite the bullet on a new rear sprocket set and/or wheel?

Bike is a Felt Six 90.
 
Could be your pedals crank, maybe the bearings making some noise. I've had noisy crank before just oiled the joins without even opening anything up. Fixed clicking noise in the past that way. Long shot but possibly could be the issue.
 
PC777 said:
Could be your pedals crank, maybe the bearings making some noise. I've had noisy crank before just oiled the joins without even opening anything up. Fixed clicking noise in the past that way. Long shot but possibly could be the issue.
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As far as I'm aware all the bottom bracket/crank, including pedals, have been checked over (two different bike shops) - all the bearings fine, no signs of wear, everything ok. This is where I thought the sound was originating from, but it does seem to be coming from the back end.
 
If it matches the rotation of pedals does it not have to relate to the pedals/BB/chainset rather than the back end?

I have similar in certain gears and I’m fairly sure it is the chain catching the front derailleur (maybe chainset is warped slightly). I haven’t been able to adjust it to not do this without affecting the shifting or causing issues in largest chain set (3x chain set), but it was a £200 bike so have resigned myself that it isn’t worth the cost of a bike shop investigating.
 
All your crank bolts and chainring bolts done up properly? Not something silly like a xable hitting your crank once every rotation? Wheel all done up tightly and lined up straight? No wear on dropouts causing the wheel to be off centre slightly?
 
I've made a booboo - it hasn't got a new rear cassette, I meant the derailleur - I didn't realise the cassette was the sprockets (the rings with teethy bits, the 'gears'!).

PikeyPriest said:
If it matches the rotation of pedals does it not have to relate to the pedals/BB/chainset rather than the back end?

I have similar in certain gears and I’m fairly sure it is the chain catching the front derailleur (maybe chainset is warped slightly). I haven’t been able to adjust it to not do this without affecting the shifting or causing issues in largest chain set (3x chain set), but it was a £200 bike so have resigned myself that it isn’t worth the cost of a bike shop investigating.
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That's what I thought, but it's been stripped down twice. It cost £220 but if a new cassette/wheel fixes it I'll go for it.

SoliD said:
All your crank bolts and chainring bolts done up properly? Not something silly like a xable hitting your crank once every rotation? Wheel all done up tightly and lined up straight? No wear on dropouts causing the wheel to be off centre slightly?
Click to expand...
If I get a chance this weekend I'll have a proper look, but the noise only starts when mild/hard pressure is used, and only in gears 4+. What adds to the issue is that it can only heard when riding the bike, I've tried replicating it while it's upside down but no joy.
 
enkoda said:
I've made a booboo - it hasn't got a new rear cassette, I meant the derailleur - I didn't realise the cassette was the sprockets (the rings with teethy bits, the 'gears'!).


That's what I thought, but it's been stripped down twice. It cost £220 but if a new cassette/wheel fixes it I'll go for it.


If I get a chance this weekend I'll have a proper look, but the noise only starts when mild/hard pressure is used, and only in gears 4+. What adds to the issue is that it can only heard when riding the bike, I've tried replicating it while it's upside down but no joy.
Click to expand...

Could be something like not quite tight enough cassette or chainring bolts. I had similar, took cassette all off and back on and resolved the issue. Same as yours only noise in lower gears under harder load.
 
Just because the BB bearings are smooth with no play doesn't mean it isn't from there.

Most bikes come dry on the threads and dry muck/salt get in there and make it super dry and creaky.

Would be worthwhile taking the BB out and greasing the threads.

Make sure your rear wheel bearing has no play, make sure it's seated in the dropout properly with the springs facing the right way and check chainring bolts. Even a spot of grease behind the dropout/rear mech hanger.
 
2 shops have serviced and not diagnosed a mere creak? I'd avoid them from now on. They should just road ride it and see the issue straight away and then correct.

As above, grease bb and crank spindle. Try some lite tight on threads, this will help a bit, but also prevent future loosening which creates wear, movement and then creaks.

Check the frame junctions for cracks.

A new chain doesn't always help btw, the old one would have worn with the rest of the drivechain. But new chains are always advisable regardless for safety.

Try checking spoke tension also.
 
Poor weather and work has prevented me from taking a look - hopefully I'll get a chance between Xmas & new year.

Thanks for the replies, I'll get back to you if I manage to find anything.
 
I thought I should update this thread:

As a last ditch attempt I found an identical replacement for the rear cassette (I noticed in my original post that I said I'd replaced it, but I meant the rear derailleur - not the geared sprockets).

It took a serious amount of effort to remove the old one but did it and fitted the new one.

And...no more clunking!

No visible signs of misalignment on the old cassette but it's cured the problem.

Thanks to everyone who offered help.
 
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