Big Rock Bearing issue... What would cause this?

[parcou]

Just not worth it to be honest. For as often as they need to be replaced and the abuse they take it will get expensive fast. Normal rubber sealed bearings are about $1 each while a good ceramic bearing will set you back about $10-20 each.

Newbie question as well...what I am researching some say the seal can melt in the motor on sealed bearings so to use metal bearings like the ones JimBearings sells for the 3S models....

 

[slick2500]

Newbie question as well...what I am researching some say the seal can melt in the motor on sealed bearings so to use metal bearings like the ones JimBearings sells for the 3S models....

Sounds like they were talking about standard sealed bearings, that is one reason you shouldn't use them in a motor the other is the bearings themselves were not designed for the high speeds of the motor. Motor bearings are designed different than standard bearings and the sealed ones use low contact seals to prevent this. I use TRBRC hybrid ceramics in all of my motors and I have never had the seal melt.