My plane is powered by a .19, possibly the same as WNewbury's,
though changes have been made over the years. There is nothing
actually wrong with the engine. It is just a shaker.

The pushrod idea won't work. The push pull force will still be
there. That is how the elevator works. If the secondary arm
was very flexible, it would absorb the vibration. It would
also allow the elevator to flop up and down and encourage
flutter.

The only thing that would work is mass balancing the
elevator. That is too much engineering for such a small plane.

This problem is not one to fix, but one to live with, kind of
like being short.

jenny