Carbon steerer top cap

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Carbon steerer top cap

Postby OrangeFTW » Sun Mar 02, 2014 17:56 pm

I think i have over tightened my top cap on my headset and because i have a carbon steerer and when i try to loosen it, it just spins round inside the steerer and what i think is wearing down the carbon. How do i remove the top cap without damaging the fork?


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Re: Carbon steerer top cap

Postby g00se » Sun Mar 02, 2014 23:41 pm

I had something similar happen with a Deda bung. A ledge on the underside of the top cap caught against the top of the bung before the top cap reached the stem- so I ended up over-tightening it. This meant I separated the internal expansion part of the bung which ended up meaning that screwing up or unscrewing the top cap just span the inside of the bung assembly.

I just tried unscrewing the cap while levering it up with a screwdriver against the stem - it eventually came up.

Carbon isn't that fragile - if the bung's spinning, it's not gripping tight.

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Re: Carbon steerer top cap

Postby Terrytibbs » Mon Mar 03, 2014 01:41 am

As G00se said, you're best trying the lever under the top cap with a screwdriver while attempting to unscrew it. This is forcing the thread on the bolt to put pressure on the thread of the expander. If it's only slightly stuck that may work.

If it's really stuck, in the end you could drill the head of the bolt off, pull the top cap off then unscrew the rest of the bolt. Or use the remaining bit of bolt to pull the extender out. You might damage the top cap but even carbon top caps aren't expensive

Make sure the extender isn't worn then you could try to re-fit it. I'd check with the manufacturer of the fork for the correct torque setting when putting it back in.

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Re: Carbon steerer top cap

Postby maddog 2 » Mon Mar 03, 2014 06:27 am

+1 if the bung is spinning it isn't gripping the steerer, so just pull it out.
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