Bama96 I like your breakin time table, had called yamaha and they really did not have anything other than the standard for the f4. I have never done the breakin on a four stroke outboard, but have many V8 motors. What we have found out of the V8s is that we would change oil and filter at 300 to 400 miles, then preform the oil change at the standard time when the motor gets to 3000 miles. You basicaly have one extra oil change this way, but it gets out the dirty oil from the first few hours. What this has done it takes a little longer for the motor to set in, but the motor seems to be more stable in the long run and seem to run smoother plus a little stronger. This is with HP rating from 250 thru 480, have had almost all go for over 200,000 miles in rough service. What I am thinking is to change the oil and filter after the first 2 hours then at 10 hours, but do you know if they run breakin oil in the 4 stroke motors?So any other ideas?