Autorotation bearing maintenance? - RC Groups
Shop our Airplanes Products Drone Products Sales
Thread Tools
Feb 23, 2003, 07:39 PM
Crash Test Dummy
bsumpter's Avatar

Autorotation bearing maintenance?

Hey everyone.

I was just wondering if there were any tricks to the autorotation bearing as far as keeping it in good operating shape. Is this something I should oil regularly? At all?

This is on an EP Concept if it makes any difference.

Sign up now
to remove ads between posts
Feb 23, 2003, 08:00 PM
spin em up
I am not to familiar with the EP but I do know that on my Eco it is a good idea to glue the bearing in the case becaue they tend to come loose and this will result in loss of power. If your EP has an alluminum bearing case this won't be a problem. And yes I think it is a good idea to use a light weight oil in the bearing.
Feb 23, 2003, 09:28 PM
Registered User


I believe that Tohru shimizu emailed me once saying that the auto rotoation bearing on the EP concept was basically bullet proof. Whenever I replace either the main or idle gear after a crash I take a look at it but it is always clean and smooth. I've used the same one since about 1998
I think that it only gets used when the blades spool down.No much time for wear ?
I've only autorotated twice in my life. Do auto rotate a lot ? Once was when my BEC leads broked mid flight and the other other happened when the idle bearing failed.

Feb 23, 2003, 09:46 PM
Crash Test Dummy
bsumpter's Avatar
Thanks for all the good info. I'm nowhere NEAR ready to even try an autorotation right now, I just wanted to make sure I wasn't forgetting some vital component maintenance. Other than my Concept 30, this is the first heli I've owned with an auto bearing in it. The EP gets flown a lot (3 to 4 flights daily, weather permitting), and I didn't know if it was a trouble spot or not.

Are there any high wear areas of the EP I should be aware of?
Feb 24, 2003, 02:13 AM
Registered User


Well, excluding crash damage I think that one weak point is the
stock tail drive pulleys and the bearings used in the idle gear and
tail belt drive. I managed to wear the teeth off the pulleys and so
did a friend. I had bearing failures at both the idle gear and the
tail belt jack shaft. All the other failures I had were directly related to
crash damage. Otherwise it is remarkably reliable.

Feb 24, 2003, 10:17 AM
Registered User

In response to your question about things to look out for on the EP Concept.

I had a Concept 10 (gas version) which I crashed 3 timed before I figured out what had happened.

In each case the tail drive quit and the heli pirhouetted into the ground.

In each case the tail boom received considerable damage, but it was unusual in that the boom looked like it had been pulled forward.

I was able to determine that one of the bearings in the tail had seized. This caused the belt to compress the tail boom and of course lose all tail authority.

This failure was intermittent, on the ground there was nothing obviously wrong with the bearing.

Just someting to keep in mind.