Originally posted by Blakesrc
The bearings in the front steering knuckles will more than likely take the most abuse from head on crashing. The 4 bearings in the rear uprights shouldnt be so bad unless you are drifting into walls and smacking them sideways. If you are worried about damaging them, i would install all of them except for the front steering knuckles, you will still notice an improvement with all the others installed.
It was me that suggested 15-20 runs in the car to break them in. Run them as you got them from Acer. Do not remove any seals, do not hit them with motor spray and do not relube them. Run them as they are. And yes, that's 15-20 packs while in the car running on the track. Run the car like you would normally...no need to baby it.
And you are not necessarly breaking in the bearing itself, you need to break in the plastic seal that Acer uses. Yes, when the bearing is brand new, it will not spin as free as a metal sheilded bearing but once broken in, the plastic will offer less resistance, spin more freely, keep the bearing much cleaner and require much less maintenance. Keep in mind that once a metal shield is dented, the bearing is shot. Since plastic will regain it's shape after a crash or incedent, the Acer will be less prone to failure.
As far as ceramics being more fragile, I have yet to see evidence of this. I will guarantee anyone that if that if they hit something hard enough to destroy or ruin a ceramic bearing, that a metal bearing,in the same kinda crash would also be destroyed. I hit the boards as hard as anyone and in over 2.5 years of using Acer Ceramics in my TC3, I have never needed to replace one bearing and i used to have to replace at least one Teflon wheel bearing (that came stock with the TC3) once a month.