I'm running the Yamaha V-Max with the 25-T1 on my 2005 Ranger Z-21 (no Jack Plate) and have a top speed of only 63 mph (GPS) with 400#s of fishermen and full fuel tanks. The engine will only turn 5,100 RPMs.

Shouldn't I be turning more RPMs with this motor/prop combination?

Shouldn't this boat be able to run near 70 mph?

Also, the motor has been contrary to start since I purchased it new in 2005 but seems to have been worse after the recall to increase the oil injection quantity. It will always immediately crank but dies whenever you give it any throttle. I usually have to start it at least 3 times before I give it 3/4 throttle, crank the motor, let it "race" for a few moments, then let it settle back into an idle. Doesn't matter if the boat has been sitting for weeks or just a few hours while trolling, it always requires at least 3 cranks to get it going.

Has anyone else experienced this problem with the HPDI?