Steering with the rudder while under power, the rudder hits the propellor if its put too far to port. Steering with the motor, one is confined to sitting toward the stern within reach of the motor. To solve both problems, I rigged a link from the rudder tiller across to the tiller of our Evinrude, slaving the rudder to the outboard, and visa-versa, so that when I put the boat's tiller over, the motor follows. This results in smooth and responsive steering with the rudder while under power.
I use the same tiller extension I use when under sail, and, because the
propellor turns away from the rudder when the helm is pulled up, the
prop doesn't hit the rudder when it's kicked up for shoal draft. The
rig also permits using the boat hook as an extension of the outboard
tiller handle when the rudder is shipped.
Different makes of motor will require different solutions for the
attachment of the link to the motor. I used a telescoping mop handle
($.50 at a yard sale), cut to the approximate length
between the motor handle and the tiller, with a 1/4-inch hole through each
end. Attaching the rod to the tiller is easy: drill a 1/4-inch hole through
the tiller (top to bottom), place the rod on top the tiller, and secure
it with a pin. (I use a trucker's hitch pin.) Behind the twist grip
throttle assembly on the motor tiller I secured a 10-inch length of
scrap tubing with two large hose clamps over a rubber bushing.
Through this tube (top to bottom) I drilled a 1/4-inch hole to which the
connecting link attaches with another pin.
The link can be quickly set up or disengaged. The telescoping rod allows alignment of the rudder with the motor for minimum drag. The motor tiller handle on the Evinrude is so shaped that the small tube on the motor handle angles inboard from the axis of the handle. When the rudder is shipped, I slip my boat hook over that tube so that I can steer using the motor while sitting or standing forward in the cockpit or even up by the mast.