Hi Paul,

I have repaired my KR400 and KR500 for the same reasons. After inspection I found out the rotor was very dirty inside.

On my website I have the pictures of the cleaning process, it gives you a feel for what to expect:

http://www.qsl.net/pa3guo click on Rotors click on KR400 or KR500 in the submenu on the left

Preventive maintenance: yes - but I admit I don't do that :-)

ps: I find my rotors noisy as well, even after cleaning.

Success ! Henk, PA3GUO

The issue I really have is should I strip them down? Both have quiet operation C/W and elevate but both are nosier on return CCW and descend. I checked the bearings on the elevation unit through the inspection cap and under the terminal screws and they look fine, shiny and greased. I'm unable to check the azimuth unit without cracking it open. What's the feeling on preventative maintaince on these units?

Paul Luggar