I'm replacing 5/32" caged bearings from both top and bottom races on my headset. The cage has 16 bearings.

If I'm going to use non-caged bearings, what would be a good amount? Is it just as simple as 'put as many as you can in, minus 1'? Have 21 in both top and bottom currently.

That's fine - do it. Just be sure to use all new bearings.

I'd put as many of the existing size in that will fit, with there still being a minimal amount of space left over. Put them in first without grease and count.

Yes, it's that simple. With headsets, put as many balls in that will sit in the cup without jumbling, and then remove one ball. With loose-ball hubs, bottom brackets, etc you should put in as many balls as will fit without jumbling, and that's it; don't remove one. Loose ball headsets will bind and not work smoothly if you use the same method as with other bearing assemblies on the bike.

Yep, I redid the headset, instead of 21, I fit 25 total. I should have known better, but this was my first loose ball headset. Thanks for the help everyone.

Put them in until the "Jumble" and then remove two. That usually means 25.

Yes, for headsets n minus two with "n" being the number of balls that has the cup full with one additional ball not able to sit down in the cup correctly (the "jumble"). Or just fill the cup to capacity (all balls sitting in the cup correctly with room for no more) and remove one........ Same thing, different words.

You're right. I just wanted to say "jumble". That's what it says in the book.

I don't quite understand why the headset should have one fewer bearing than hubs and bottom brackets, but I'll take your word for it.

I think as a general rule, loose bearings need to be put into a race minus 1. You don't want bearings to completely fill up a race otherwise there would be too much friction causing problems.

No, loose-ball hubs for example should have as many balls as will fit in the cup without jumbling. Bottom brackets, too. Headsets are different in that they tend to bind and not be smooth unless you remove an extra ball.

I don't blame you.....it's a cool word.

Shimano certainly doesn't agree with you for their hubs.

Well i am just learning. So I have learned something new. I just am thinking in general whenever I have dealt with loose bearings in the past. Like bearings on my moped or old ATC three wheelers. I always put as many bearings as I could in the race and then when they filled it up to the point where they started to push each other, I would remove one of them..

Hmm... maybe it has to do with the fact that the headset doesn't rotate completely like hubs and BBs and the bearings sort of settle into an optimal place for short movements?

After all this discussion, I now would like a real logical scientific mechanical reason for removing one or two balls.

If the reason is that since the headset doesnt turn clear around, and the balls will stay in the same place and wear, what about caged bearings. The cage will stay in the same place, so that reason doesnt seem valid.

Maybe the reason is because the headset is the only bearing that is regularly reversing direction? And it is important that this reversal happens smoothly.