I just put in a D-plate. And adjusted the Highs all to 1-1/4 per RIVA instructions. Now the ski will only do about 54MPH and this is at 3/4 throttle full throttle it slows to 50. WHat gives? THe plugs on 1 and 3 looked great 2 was a little lean but not that bad. Any ideas? Its not easy to mess with the carb on these boats (I gotta pull the whole stinger out) so I would like to get it right for next time.