I have a 2006 9.9 4 stroke merc on my grizzly 1448 sc. I changed from a 8.5 pitch prop to a 6.5, rpms went from 4300 to 5300 WOT for 8mph gps. I was happy with that, being that I am now within the 5 to 6 thousand rpm rating for this motor. Now, the 5300 is with my buddy and me plus 2 batteries and gear. By myself, rpms go to 6030 WOT for 14 mph gps. Will this hurt my motor to keep WOT for only 30 rpms over, or should I back off throttle some, or just add another battery, ect. ? Thanks