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Diagnosing CSU crea...
 

Diagnosing CSU creak

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[#12859063]

My old bike is creaking intermittently.

It comes and goes, and seems to start after I’ve done two decent sized drops at the end of my training loop. I’ve greased suspension pivots, the bearings are relatively new, the headset is ok and fully greased, the bottom bracket was replaced relatively recently.

I’m starting to wonder if it’s the CSU in the fork. Obviously if it is it has some pretty serious implications for the bike, as most of the parts are well used, and so if the CSU is creaking it’s probably time to stop riding it. Is there any way I can test this?


 
Posted : 18/06/2023 9:45 am
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Rockshox can creak if the top caps aren't torqued up correctly.

Some places offer a service where the stanchions and steerer and pressed out and rebonded.


 
Posted : 18/06/2023 11:12 am
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Can you get it to the point where it would normally make the noise and squirt some water on the bottom of the headset. That might stop the noise briefly and at least confirm it.


 
Posted : 18/06/2023 12:55 pm
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Thanks both.


 
Posted : 18/06/2023 12:59 pm
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The fork is a 6 year old non-boost pike that has seen some action, not sure it’s worth the effort of rebonding it.


 
Posted : 18/06/2023 1:00 pm
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If it's that vintage, then definitely check the top cap torque. They were buggers for working loose and clicking.


 
Posted : 18/06/2023 1:02 pm
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It’s a mountain bike suspension fork, odds are it’s the CSU as no one seems to have figured out how to make one that doesn’t after all these years.


 
Posted : 18/06/2023 2:39 pm
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Any idea what the top cap torque is meant to be?


 
Posted : 18/06/2023 2:49 pm
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Dunno, I'm sure it'll be on one of their service videos.

If you want conclusive proof. Remove the fork and drop the lowers.

Fit an old stem to the steerer, put it in a vice and give the stanchions a push/pull.

If nothing else It'd be a good excuse for a service.


 
Posted : 18/06/2023 2:59 pm
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Thanks, I’ll give that a go.


 
Posted : 18/06/2023 3:12 pm
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28Nm rings a bell, which feels pretty damn tight when you're doing them up.


 
Posted : 18/06/2023 3:48 pm
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Pull the fork off and clamp the steerer in a vice, if you get get it to click, it’s the csu. If it doesn’t, good be any part of the cockpit


 
Posted : 18/06/2023 6:21 pm