maintaining a headset
 

How do I do this? I opened it up and the cap is unremovable, basically it appears rusted in place. Should I be able to remove it?

What kind of headset? Threaded or threadless?

threadless.

Yes, the top cap should come off easily once the top nut is removed. Then the stem and all the spacers should slide off in sequence once the stem clamp screws are loosened. After that the upper bearing and centering cone, allowing the fork to drop out of the frame.

I doubt rust is holding the top cap on, but just in case, put a small screwdriver under it at the stem's slot and give it a gentle nudge.

Remove the star-nut bolt at the top, loosen the stem's pinch bolts or remove the stem all together, and give the steerer tube a downward whack with a rubber mallet or a regular hammer and block of wood.

There really isn't a whole hell of alot to do to a threadless headset beyond perhaps cleaning it and giving it some lubrication.

http://www.parktool.com/repair/readhowto.asp?id=65

oh okay. I was under the impression that the little star-shaped thing inside the fork had to be removable. So just lubricate them and done? no ball bearings toworry about either?

yes, consider the starnut a permanent part of the fork, whose only job is to provide a fixed point for the top cap screw to attach to.

And no, there are ball bearing assemblies, which is what you're lubricating, depending on the headset model they're either loose balls in retainers (make sure not to flip over) or cartridge bearing units, which for all practical purposes are not serviceable, except for the fork or bearing play adjustment.

Keep track of the sequence and orientation of the parts if you disassemble the headset, and follow the primers offered by Park Tool or Sheldon Brown at their sites.