Bicycle Mechanics - Chris King Headset Gap

I recently purchased an 1 1/8" Nothreadset for my roadbike, and had my LBS install it. A little later, I switched out the stem, but I can't get the bearing cap to seal tightly like it was after the LBS installed it. When I'm all done putting it back together, there is no play in the headset and it seems to glide just as smoothly as before, but there is a small gap between the bearing cap and the race. And I'm fairly certain it was snugger when the LBS did it the first time. The gap seems to be slightly larger in the back than in the front.

I read two other threads that talked about it, and it offered these two suggestions:

The cable hanger may not be a uniform thickness- not it, i have tried without the hanger at all.
I also tried using the original stem in case it was that.

The bearing cap is not being pressed on evenly- possible. I am pressing as hard as i can but once it's right down near the race, it won't budge.

Also, the way I am able to get the gap the tightest is to suspend the front end off the ground, not with the wheel on the ground.

If anyone could help me out with the right way to do this I would really appreciate it. I am planning on going back to the LBS and asking for help, but it'll be a week before I can get there and plus, it's hard for me to leave it alone. I just want to get it.

Thanks in advance

Ralph

Okay, this is in case someone has the same problem as I did and nothing seems to work to fix it. I also want to be a little more specific about when the gap would appear. Everything would line up just about perfectly before I tightened the cap, but as I tightened the cap, the front of the bearing cap would snug down and the back would slide open.

My bike is a 61cm '08 Bianchi San Jose with everything stock except the CK headset, if it makes a difference. I ended up taking it to the LBS and these are some things they tried:

Trying a different fork
Checking the level of all parts related to the headset (both on the bike and the headset itself)
Refacing the steering tube
Using a different stem cap
Using no cable hanger, just more spacers
Flipping the stem over
Using all spacers and no stem or hanger
Using a different stem without the hanger
Using a different stem with a different hanger

The only things that made a difference were the last 3. So as odd as it seems, there was some discrepancy between the stem, hanger, fork and the CK Headset without any one of those parts exhibiting any serious defect individually. I am ordering a new stem and hanger in a little while and I will post back with the type of parts and results.

Hopefully this will solve the problem.

Ralph

Without a picture it's hard to diagnose your problem, but it sounds like your new stem is not the same stack height as your old stem. When done properly steertube should be 3mm lower than the top of the stem so when you tighten down the topcap you are applying pressure to the bearings.

Scroll to the bottom of the page here for directions on how to adjust your headset:
http://www.parktool.com/repair/readhowto.asp?id=65

I wish I had pictures to show also. Sorry about that. The stack height for the new stem is just about identical. The spacing is about 3.2 mm. Could that little bit be making a difference? I will look into trying to get it even closer.

Thanks

and thank you for the link :)

I relooked at the list of everything that's already been done and I don't see putting a spacer above the stem. Have you tried that?

Yes, sorry I forgot to add that. I tried putting the stem on and then all the spacers as well as just one spacer above the stem.

New stem, New cable hanger= fail
I am going to order a new fork, and see if that does it.

I noticed some horizontal scoring on the steer tube about an inch down from the upper crown race. don't know what would have caused this.