How many bearings ?

[Mr Pig]

"you can get another one in but don't"

I'm not saying that's wrong, I have no idea, but the reasoning doesn't convince me. It's not as if there is anything holding them equidistant, they'll touch each other just the same as they would if there were more of them.

 

[Yorkshireman]

I'm not saying that's wrong, I have no idea, but the reasoning doesn't convince me. It's not as if there is anything holding them equidistant, they'll touch each other just the same as they would if there were more of them.

It might be the case that if the balls are forced to touch all the time, that that's what causes them to bind and break up, whereas if they have room to move a bit they will 'find their own place in the scheme of things' so to speak. As I understand it the balls should have the main contact between the cone and the cup, and if packed tightly together the cone would not be able to be adjusted properly ie the bearing would be in effect a plain bush bearing - but not as good as a standard plain bush ... maybe?
I'm not an engineer, but I did work on heavy plant (earth movers, pavers, road rollers etc) both as an operator and as a maintenance/repair man for a few years, and bearings used in similar systems seem to have been the same from what I can remember.

 

[Mr Pig]

I just came across this, thank you to the guy who pointed out the site. Note that he says there should be 'half a bearing space' left:

http://bicycletutor.com/overhaul-wheel-bearings/