Amram,

This is totally normal. That is the purpose of the LR mount (limited rotation). At idle the engine is essentially hard mounted. This helps SIGNIFICANTLY with the low idle. The problem without the limiters is that the engine bounces around too much and unless you have the throttle servo attached to the mount the rotational forces will move the throttle just enough that you can't get the ultra low idle. Stuff bouncing around a lot at idle isn't nearly as sigificant as it would be at a much higher throttle setting. As soon as you start to advance the throttle and and the mount stretches, it moves off the stops and you get the full Hyde soft mount effect. I flew this mount all last year and this spring. I recently pulled all my servos to be send back to Futaba. With close to 300 flights, NONE of them needed the pots changed. They are Futaba BLS-154's, 254 and 352, so the mount is still doing its job, it just dances a lot with the idle ultra low. Mine really starts to shake with an idle of 1500 or lower. I can make mine idle consistently at 1350, but you can really see the plane dance as it is firmly sitting on the stops.

Arch