X12's... ive found do run hot.. and i have had one bearing failure...
If you have the early X12's make sure you have the " .... " timing bit in to make it zero timing.. early ones had the " .. "
Also as the temps are high, it can dry the bearings out... so after every couple of meetings i remove the bearings and oil with some good quality oil..
You can buy a special bearing remover tool from LRP and its takes no time at all to do
Just make sure you dont over do it with the oil.. oil them, leave for a few minutes then spin them on the rotor wipe excess of then put back in place..
No motor is maintenance free... if you want them to last, maintain them.. anything with moving parts needs TLC some more frequent than others.. in the case of bearings the hotter they get the more regular you should maintain... common sense really
When brushed were around... you always were taking the can to bits to sort the comm etc and you would clean it as it was in bits... well i did anyway.. this would include oiling bearings etc which is probably why we didnt get bearing failures?
Cheers
Nick