motor bearings

[fastblack]

how often do you change the motor bearings? i have leopard 4074 motors

do you have too oil these bearings? they a cheramic bearings arent they? do they need oiling?


i run 1400kv at 8 cell
41500rpm

and

2000kv at 6 cell = 44000rpm

loaded rpm should be about 5000 lower than unloaded, do you guys think this is too much rpm for the motors?

the 1400kv is a 4-9s lipo motor

the 2000kv is a 2-6s motor

[m4a1usr]

Bearing replacement/ oiling is dependant on motor wear. If you run it hot, or with an unbalanced coupler/ shaft its going to wear faster then taking the time to do it right. Since most factory motor bearings are grease packed, oiling is important once the grease thins out. What most of us do is after each run is start our maintenance cycle, when you pull your flex off to dry out and regrease you can add a drop to front bearing. The back one does not see as much load as the front one.

The only way to know when to change out your bearing is to inspect it for wear. The best method for bearing inspection is to take the motor out of the hull, remove the screws from the front motor/bearing plate and pull it out of the can enough to spin it by hand. Spinning the rotor in the can doesnt provide enough feedback to accurately tell you when the wear is sufficient for replacement. The rear bearing doesnt wear as fast as the front bearing due to axial loading.

The bearings in a Leopard are not ceramic. They are caged steel typically of enough quality to spin high rpm's but I wouldnt trust them for any significant time frame. You want to spin high rpm's change them out to better quality ones. The bearings in my Leopard 5692's were changed out right out of the box. I didnt like their quality and needed to be replaced.

John

[Fluid]

The back one does not see as much load as the front one.

John, for those who do not use thrust bearings (most users) this may not be the case. The front PTO bearing only handles radial loads, the rear takes axial loads as well. Anyway I seem to replace more rear bearings. I agree with the Leopard bearings, I too was not impressed. But Leopard had to reduce costs somewhere, and since those motors were designed for the car market they can get by with less costly bearings. Boats can be hard on bearings.


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