trust me you will notice. it feels very notchy, and the engine just stops performing.

feel the bearing after every race day (the outside, and the inside individualy with your finger) it will feel notchy, or rough, or gritty if it is either dead, or about to die.

if the internal ceramic bearing feels rough or notchy (it should be totally smooth) then change it ASAP if the ceramic blows it will destroy the internals of the engine.

i think it is mainly the outside (small bearing) that dies though.