Like many of us, I started out with cup and cone hubs. The idea of adjusting the preload on angular contact bearings makes perfect sense.
Then we move forward to cartridge bearings. We even covered the design of them at Uni and it made sense. With two bearings in a device (bottom bracket/front hub) then you leave one of the four bearing races to float and the alignment takes care of itself.
Now, I’ve head cartridge bearing die or fail in different ways, but I’ve never replaced one due to excessive play. Normally the rust, fill up with mud, feel too lumpy or just disintegrate.
So, cartridge bearing hubs with preload adjusters – I get the theory and it makes sense if they’re using angular contact bearing – but has anyone found adjusters useful on hubs with normal deep groove bearings?