bearing cap install (headset)
 

Hey all, I just slid the bearing cap onto the steering tube of my fork. I can get it down to where it's about 2mm from being flush with the bearing cup. It's a chris king nothreadset by the way. Is it supposed to sit a little above the bearing cup or is it supposed to sit on top of it? It doesn't look right, but logically I guess it makes sense because if it sat flat against it the two would just grind at each other (may have just answered my own question right here). Anyway, chime in if you can confirm this or know anything about installing these. Thanks a lot, Andrew

Anybody anybody? Should that gap be there between the bearing cap and upper cup? I don't think it should because as snug as the bearing cap has made the fork there's still a little up and down play in the fork. I tried smacking it down further with a pvc pipe and mallet but won't go down any further.

Gap shouldn't be there

It should look like this. http://chrisking.com/headsets/hds_nts

Got a headset press? preferably with a set of CK made fittings for the headset press
to keep the cup's top edges from being damaged..

Might need the head tube reamed and faced.

I don't see why the headtube would need to be reamed. I already installed the upper and lower cups. It's just the bearing cap that slides down the steerer onto the upper cup is not going all the way down to the upper cup. There's a small gap there.

I'm thinking either I should slide it up a bit and put a light film of grease on the steerer just above the upper cup to help it slide all the way down, or just hope that when I tighten the stem cap screw it will push it down to the upper cup.

Sounds more to me like something isn't seated right into the cup. The bearings in my Cane Creek headset have a beveled edge on one side, if that edge is facing up rather than down into the cup the way its supposed to be, I can't get assembly right. So you might try opulling the cartridge bearing out and reinstalling to make sure it is fully and correctly searted in the cup.

To be honest I think there's supposed to be a very small gap. I pulled off the bearing cap and pulled out the fork and placed the bearing cap on top of the upper cup and there's still a very small gap. It wouldn't make mechanical sense if the cap was flat against the cup. The fork wouldn't turn well at all with metal against metal. So the gap is normal and the very minimal up and down play will most likely be fixed when I tighten down the stem cap. Just looked wrong at first but it actually makes sense now. :thumb:

CK bearing cartridges are spun into their cups so they can't be removed. Also, CK relies on an O-ring in the top cap to keep everything centered and doesn't have a split cone ring like other headsets.

To the OP, the top cover on my CK headset is complete flush with and actually fits slightly inside of the top bearing cup with no decernable gap.

Ah, learned something new today. What is benefit of unremovable bearings? And could OPs gap have something to do with wisaligned O-ring? 2mm seems a bit much to be normal.

The "benefit" is to CK, I guess. You have to send the headset back to them for repairs or replacement. Maybe it assures the bearings are installed and aligned properly. The bearings can have the seal popped out and regreased in-situ if you want to bother. Fortunately they have a 10-year warranty and I haven't had any problems with mine in 5 years so far.

The O-ring is a tight fit on the steerer tube and can be knocked out of it's retaining groove in the top cap if you don't install it carefully. King's installation instruction sheet particularly warns against this. I filed a slight bevel to the outside top edge of the steerer tube and put a little silicone grease on the O-ring to make the top cap installation easier.

hey hillrider, when you spin your fork does the bearing cap with the o ring turn with it or does it sit stationary? I'd imagine it turns with it because it's such a snug fit around the steerer. If it is supposed to turn it would make sense that there's a gap (metal on metal would be very inefficient). But if it's supposed sit still then it would make sense that it should be snug against the upper cup.

The gap by the way is closer to .5 - 1 mm, not 2mm.

The top cap does indeed turn with the bars and steerer while the cup is (obviously) stationary. However the annular clearance between the top cap and the cup is extremely small and nearly invisible. The fit tolerance is very precise.

ok thanks for the reply that clears things up a bit. So a very minimal gap is expected. I think when I tighten down the stem cap screw it should seat it down properly. Waddayathink?

Try it and let us know. CK does recommend a modest preload on the top cap bolt of 4-10 inch-pounds with a maximum of 15 inch-pounds so don't just get the bolt finger tight.