kraftwerk 

Seized ! Carbon-spacer has fused to the head tube (!) Both are un-finished, unpainted carbon. Originally a very tight fit, it's been on there for about 6 years.
Now I am stuck ,since the head-set can't be serviced, I can't change the spacer or even tighten the head set.
it is actually fused in such a way that the spacer sits slightly above the headset race, so there is a gap. Otherwise I would leave it alone.
The spacer is now essentially welded to the head tube, and it's in the wrong 'place'.

I can tell you what hasn't worked: tapping the top of the head tube to push the fork out with a rubber mallet.
REALLY tapping it - giving it a good WACK or two.
Water- sprayed. Soapy water, sprayed.
PB Blaster - actually this makes it worse: solvents further break-down carbon and make it stick even more. Don't use solvents on carbon.

Anyway, the loose head-set, the gap is pretty slight.. so it's annoying when noticed but but not super-loose, I think, over the years, the carbon spacer has worn away a bit where the head set race slides under it causing slight wear, causing a 'gap' - about the size / thickness of a thread, so not a big enough gap to really 'work with' to remove the spacer.

Totally stumped...

Barry2 

Given that it's not my bike so I can be really brave!!!!
Cut the spacer.

Barry

ClydeClydeson

Barry2 is correct - destructive removal of the spacer is the answer, just be damn careful not to damage the steerer tube underneath.

Barry2 

To be a little more constructive (destructive)... I'd cut across the height of the spacer, slip in the biggest screwdriver I could and twist.
Just DON'T try to cut through the full thickness of the spacer.

Barry

kraftwerk 

yes...Dremel tool.. going to be a delicate operation...

Barry2 

If you're chicken... Buy your machinist buddy a six pack and gently stick it in the mill.

OH... and I'd use a hand saw before I'd let myself loose with a dremel.
With a Dremel you can screw up in a flash.
With a hand saw you can enjoy a cup of coffee while you're screwing up.

Barry

Andrew R Stewart 

And this is why it's good advice to periodically take stuff apart and reassemble, even if there's no outward indication of this need. Andy

cxwrench

Solvents break down carbon? That's news to me. The spacers shouldn't be sliding against anything. They move w/ the fork/stem/spacers.

70sSanO

Step 1, is a replacement fork available?

John

kraftwerk 

Okay... so before I unleashed the dark forces of the Dremel tool, I thought to spray more soapy water on it then
ever so gently ( if you can even use that word here...) I clamped a vice grip around the spacer, just enough to 'bite in' slightly..
and with more soap-spray, I was able to turn the spacer on the steerer-tube (!)
Spraying soapy water, I slowly rotated it off the fork-tube using the vice-grip. The spacer just has a few bite marks in it but nothing was greatly harmed.
The grease on the sealed bering FSA carbon headset is jet black , like tar.. so it was originally black grease or is just really dirty..
time to clean.

kraftwerk 

The spacer should only move when you want it to come off. In this case, slight correction, the spacer, stem, and handlebars moved together as they normally should, with top of the headset-race, but some wear occurred, somehow, over about 6 to 8 years and head-set adjustment was finally needed.
Yes: solvents will degrade or sludge-off a slight layer of raw un-treated carbon, try putting some PB blaster on paper-towel then rub some carbon,
the carbon will come off onto the paper towel. This won't happen if the carbon is coated, it only slags off raw carbon & slightly but still not good.
The inside of a carbon space is not coated anyway nor is a carbon head tube.
Solvents liquify the powdery layer of raw carbon fiber that's why most carbon fiber items will have a matte or glossy top-coat or be painted.

I cut my own custom-sized spacers out of a length of raw carbon tubing.
If you cut a carbon spacer you usually need to sand it down a bit, use a piece of sand-paper on top of a piece of glass,
(like when you "deck" cylinder heads.)
Wet sanding here is a good idea to keep dust to a minimum, nasty stuff.

shelbyfv

Maybe not the best choice?

bikemeister

Shoot, I never knew any of this with carbon fiber components. I thought carbon was pretty inert.

I had a friend whose aluminum seat post was seized into his titanium seat tube. He finally got it out by taking it to the bike shop. Guy said he had to use a titanium post on a titanium frame to prevent any galvanic-type reaction. Don't know if that was a selling scam but he didn't have problems after that.

kraftwerk 

Andrew R. Stewart is correct if I overhauled the headset on the regular (every two years?) or so I probably wouldn't have had this issue. One thing also I put that
particular spacer aside and was able to find a 'commercially made' carbon spacer which slid on with a bit more ease, not as tight and will be easier
to remove next time.. sooner than later.

Barry2 

20:20

Have you cut it yet?
enquiring minds……….

Barry