Originally Posted by
Street rider
I'm going to say it again, because I don't know that you read my post. Good luck pressing sealed bearings into hubs that have cones for unsealed. You'll ruin the bearings, and probably the hubs somehow in the process. Unsealed is better anyway, just requires more maintenance.
He doesn't say anything about trying to press in sealed bearings, which would never work anyway. How are unsealed better? Sealed are more expensive, but last longer, no problem with adjustments, no maintenance, stronger...
On a BMX bike, ceramic bearings are not going to make a difference. Just replace the steel ones if they need to be, use the Park grease you have, and adjust them properly.