[Closed] Cracking/creaking headset

Hello all. I've never posted before, but have greatly appreciated (and made use of) the fixes and solutions presented by other members on here. Hence I thought I'd share this in case it is of use to anyone else. It's put years on me.

I have a 2010 Specialized Enduro. For about 4 months I've been plagued by a sharp cracking sound from the headset area every time I stressed the headset (braking, endos, landings etc). It's a carbon bike, so I was worried, and it was getting louder and more frequent.

I found a useful test- by popping the bike onto the rear wheel, pulling the rear brake and turning the bars through 90 degrees, I could lift one bar end while pushing the other down and occasionally make the cracking sound. This convinced me it wasn't the fork.

I stripped, greased and rebuilt the integrated headset- nothing changed.

I replaced the upper and lower cartridge bearings - no change. I checked the spec on the bearings. They were correct.

I replaced the expanding nut style steerer tube top cap holder with a steel star nut- this really helped me torque up the headset, but it still didn't help- the crack was, if anything, louder.

I took the headset apart again and inspected it- I could see galling on the surface of the lower bearing and the spacer needed when you use a non Specialized fork on an Enduro (the Specialized fork has an integrated bearing race at a different height). I could see one tiny mark on the top bearing seat.

So I rubbed them down lightly with wet and dry, greased and re-fitted. No change.

I then went to my LBS- they glued the lower bearing and spacer in. No change. I was ready to give up.

As a last attempt, I took the headset apart again- and pushed the top bearing into the seat with my fingers and tried to rock it. I sort of convinced myself it rocked more fore to aft than back to front. I bought some Loctite 641 bearing seat (medium strength) and glued the upper bearing in. Fixed. Silence. Three hours riding without a sound audible above my panting. It couldn't do it for 3 minutes the ride before.