andrew9 wrote:The price for those ceramic bearings is just crazy, wow.
You could try carefully picking the seals out of the 4130 and flushing and re-greasing. You could even leave the inner seals off, for less drag, but it depends on how well sealed the BB area of the frame is, as to whether that will affect durability.
My lightning BB86 cups, fitted with four $5 ebay metal shielded bearings spin quite nice. They're not as free as a nice old loose ball square taper BB, but about the same as my other bikes Ultegra BB-R60.
I serviced them after 2000 kilometers, as I am concerned about their durability. I had another set of bearings ready to go in, but all four bearings were still very good, just cleaned off and greased the outsides of the shields
There is a discussion on BB86 bearings for 30mm spindles:
viewtopic.php?f=113&t=132784
Thanks for sharing your solution.
The problem for 41/30 is that we need 2 bearings per side, so, a total of 4 bearings per BB. That's twice more than standard BB.
With twice more bearings we may expect twice more friction and that's probably a reason of the bad smoothness of Rotor 41/30 Steel and Gold.
Moreover, BB manufacturers are selling OEM cups at high prices so that ceramic manufacturers need to sell at a higher price the complete BB.
But honestly, when you see coated bearings or jockey wheels in a price range $300-400, a good ceramic 41/30 BB at $250 is a good deal when you know that you can use the best 30mm cranks in the world and take the benefits of stiffness and lightweight. On cyclingceramic BB, we have been observing a life duration longer than 2 years on all the products. That's because there is no compromise on any of the components of these bearings.