Temps on the motor shaft?

[bdebde]

I was running my 1/8th buggy today, pretty warm day. My Lehner 1930 temped at 165. I touched the motor shaft at the back end and it was HOT, temped it at 240. Just wondering if others have seen this, or if I am having bearig probs already (new motor). If someone has a chance, take a temp on the shaft at the rear and see what you have. Thanks.

Also what do you guys do for bearing lube/maintenance?

[MetalMan]

I think this has to do with the inside of the motor being hotter than the outside (obviously the inside would be hotter), as well as the friction from the bearing causing greater heat buildup. Recently I saw that the back of the motor was about 10 deg. hotter than the can, but this was on the endbell (I have tape over the shaft to protect the bearing).

[SpEEdyBL]

Sometimes the rotor magnet can heat up. The same thing happened to my 380c 9t motor. I found out that it was the rotor because I ran the motor for about 30 seconds, opened it up and the rotor was warm. The rest of the motor was cool. I think this is due to iron loss or inconsistancies in the rotor's magnetic field. Im not certain though.

[zeropointbug]

Yeah, the rotor is almost always hotter than the stator is. These are eddy currents in the magnet caused by the switching coils. The Lehners and Neu won't (in theory) get as hot a rotor as Feigaos.

Preferably, if it could be done, would make very thin laminations for the magnets, to almost get rid of this completely.

[BrianG]

Originally Posted by zeropointbug

Preferably, if it could be done, would make very thin laminations for the magnets, to almost get rid of this completely.

Isn't that what Neu and LMT does (somewhat)? And isn't that a large contributing factor for the price? You get what you pay for...

[zeropointbug]

They have smaller magnets yeah, but I'm talking laminations, if it could be done with Neo mags. I would agree that's part of the price, but also, where they are made, the Feigao's are made in China, and we all know of the 'slave' labor.