Skateboard bearings are different to normal bearings by having to be exremely shock resistant.
Bearings are usually not made to withstand sudden impact hits. For this reason standard bearings would stop on impact after making an ollie over a big gap.
Standard bearings need to warm up before reaching full speed, however skateboard bearings must run at full speed from the time a skater steps on his board and pushes.
We at 2HEX have developed bearings with materials and specifications, that are perfect for skateboarding. Therefor no matter how you combine your custom bearings, each combination will be a very good skateboard bearing!
Skateboard Bearings Factory Information: