Bicycle Mechanics - Quill Stem is out, but headset nut stuck!

I am trying to remove a campagnolo headset from a frame constructed from Reynolds 653 tubing. I have manged to remove the stem, but now am unsuccessfully trying to loosen the locknut on top of the adjustable cup. The nut is in good condition and I am using a good quality 32mm bicycle wrench, but it is very tight, and I am worried about damaging something.

Any suggestions?

Are you using a second, thin 32mm wrench to hold the top race while loosening the nut? If you don't have one, hold a 2x4 or a wood handle of some sort up high in the fork for leverage and try to loosen the nut that way. Pad the 2x4 with rags.
http://www.stifsport.com/images/products/park-rw1med.jpg

yes, I am. It is REALLY tight and I do not feel comfortable applying considerable force. I have already made a slight mark on the flats of the top nut

If it is steel (of course it is), then there may be some rust in the threads preventing it from coming loose. You may want to spray it with penetrating oil and let it sit overnight. The next day try to remove it, but don't use excessive force. If it still won't come loose, shoot it again with the penatrating oil, and try again the next day.

If after several tries over a few days, it still won't come loose, then you may need to take it to the bike shop, and let them have a crack at it.

Also, it may well be useful to stick the handlebars (and of course the quill stem) back in, so you can use the bars as leverage when attempting to loosen the nut. I ususally do this. However, if too much torque is required, this may be bad for the steerer tube.

If you are not concerned with saving the paint use heat on the nut a propane torch will usually work, then use a large wrench for more leverage.

Might try hitting the nut with a metal hammer. It may jar the nut enough to loosen up built up rust, if that is the problem.

Its OFF!!

lots of WD40 over 2 days and a brace between the forks did it.

Bit disappointd that I have marked the nuts. Does anyone know how to apply force without marking the nuts??

Thanks for all suggestions

Unless you've stripped the nut, no harm in marking it. That said, the way to not mark a nut is to use a wrench that fits tighter, and has wider jaws (force spread out over more contact area).

it's a nut, you use tools on it. it's going to get marked. get over it.

Does anyone know how to apply force without marking the nuts??

Thanks for all suggestions

That's what this baby is for:

http://www.parktool.com/products/detail.asp?cat=50&item=HW%2D2

Yeh, it's a $30 wrench, but it's really a lovely tool. If you own any nice threaded headsets, this is the way to go. I'm not a CK guy myself, but if I was paying $120 for a headset, this is the only tool that would ever touch the locknut.

I suppose if you are really anal about marring you could put a layer of electrical tape on the nut before you put a wrench on it, but then you'd likely be stuck using an adjustable. I've never done that with a headset locknut, but I have done it with other things. If you are going to use an adjustable, the biggest one you can get your hands on is the best. But, again, that Park HW-2 is a great tool that's designed for exactly what you asked about.