Sorry for the delay trap, here is the info. My F200 inline 4 is mounted 3 holes down from the top. I gained 300 rpm on the switch from the Yamaha 17" SDS to the Yamaha 15" SDS. Conditions today: Light chop, full tank, 2 onboard.
Cruise which improved 4200 RPM @28 MPH, 3.4 MPG
WOT which went...