Here's a crazy question. Does it only smoke when on the sidestand or will it smoke when upright? My vintage Triumph Bonneville will do that when hot and on the sidestand. Gravity directs the flow of oil from the rocker boxes into the valve seats instead of down the pushrod tube. Oil pools up and some will get by the valve seals into the combustion chamber = white smoke. This all may sound wierd to you sohc people but it may be the same principle; oil pooling up around the valve seat and leaking into the combustion chamber because the motor is not upright. Worth considering.
Scott
