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[Closed] Carbon fork noises - eek

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[#3083210]

On my road bike (Giant OCR) which has carbon forks I'm getting a slightly alarming noise. There's no apparent cracks or delamination anywhere but under heavy braking on rough surfaces I get a crack noise like you've never heard - first time I heard it I thought the forks were off and I braced for the impact. Spoke tension seems fine, QR is tight, brakes are tight. Any more thoughts, I'm a bit paranoid now as it's getting worse!


 
Posted : 25/08/2011 3:30 pm
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Checked bearings in your headset?


 
Posted : 25/08/2011 3:31 pm
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^^ +1


 
Posted : 25/08/2011 3:33 pm
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No play in them if that's where you're going - it's rock solid. Can't tell if there's any further problems though?


 
Posted : 25/08/2011 3:35 pm
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Put grease/copperslip on the drop outs? Don't scoff. My Planet X carbon began a creak/grind terribly after a few months use. It sounded like a knackered BB or loose bits around the carnk. I tried everything, Copperslipping ring bolts, crank bolts, making sure they all fittings were tigt. It just got worse and worse. I emailed P-X and they suggested grease/copperslip on the rear drop outs. Lo and behold - no creak! Give it a go, I'm not saying it will work, but then I didn't think it would on my bike. If that don't get it in to a shop or at least totally strip everything and inspect carefully yourself.


 
Posted : 25/08/2011 3:37 pm
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Personally, I'd disassemble the whole front end. And I mean EVERYTHING: All the bolts out of the stem, every part of the headset out of the frame, hub, QR etc, then clean it all, grease up what should be greased up, and reassemble the lot, checking for play as it went back together (Headset should be tight but very smooth) and try again.

If that didn't do it I'd suspect it was a noise echoing round the frame from elsewhere, as my FSR used to creak at the 'front' when it was actually the seatclamp!


 
Posted : 25/08/2011 3:40 pm
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Looks like a fun evening of strip and lube for me then eh! It's definitely not a creak, it's an almighty crack noise, but it could be something slipping. Cheers all!


 
Posted : 25/08/2011 3:43 pm
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Is the brake caliper tight?


 
Posted : 25/08/2011 3:45 pm
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Yup!


 
Posted : 25/08/2011 3:48 pm
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I get EXACTLY this - carbon forks, ally/ carbon frame - generally when I'm going over speed bumps.
I'm kind of hoping that it's damage as I've been wanting a new road frame and forks for a while, but I also don't want it to kill me. I also don't have the time to strip it down and find the problem.
Might try the copper slip thing.


 
Posted : 25/08/2011 4:02 pm
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I had a similar problem with my Defy, All felt solid, but the sealed bearings in the lower cup had dried out and started to corrode. Rocking the bike no problem but the force of my weight on the bike and breaking along with flex caused an awfull knocking noise.

Get some lithium grease and some copper slip and strip and rebuild your front end like said above. spin the bearing in your finger you'll feel if they have "gone"


 
Posted : 25/08/2011 4:09 pm
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Found it - finally! After a quick stem inversion for comfort testing it got noticably worse. It was the bar rotating TINY amounts in the stem. Not even visible until it finally started slipping properly and moved a cm or so. Since it started slipping properly it's stopped cracking. So I guess I need to swing a little harder on those stem bolts!


 
Posted : 22/03/2012 2:37 pm
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Six months! Didn't the noises and fear drive you insane?

Pleased for you you found it without a faceplant ๐Ÿ™‚


 
Posted : 22/03/2012 2:59 pm
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It's my road bike and it's been winter - I'd only used it on the turbo trainer so it didn't bother me much but while out riding I was slowly getting a tighter and tighter set of buttocks over anything bumpy at speed!


 
Posted : 22/03/2012 4:10 pm