Lube for small ball bearings?

[larrymoencurly]

I have several very small 2,000 RPM DC fans with ball bearings measuring about I.D. = 3/32", O.D. = 5/16". What would be a good lube to use on them?

The bearings are unsealed and seem to have no lube in them, and there's not even oily residue or dust on the outside.

 

[bruce381]

#1 grease applied with a needle or syring.
bruce

 

[bruce381]

"I tried some ordinary NLGI #1 lithium grease in a couple, but the motors spun about 20% slower than normal until they ran for a few minutes."

Sounds like you over greased and upon expelling extra grease they ran normal other wise us a good quality ISO 32 or 46 hydraulic or turbine oil.
bruce

 

[Thingfish]

I use a 50/50 mix of Green German Castrol and Marvell Mystery oil on my R/C bearings.
They are cleaned and lubed with one drop ( any more attracts dust ) after every race. ( motors ) and chassis bearings after every race day. (10-12 , 5 min runs )

These motors are in excess of 50K rpm, can pull over 100A ( enough load to un-solder FETs in a high end speed controller ) and get too hot to touch after a 5 min run. ( new brushes and brush springs after every run, along with truing the commutator )