Need Help for prop on 60C PLEASE

[dallascarstore]

I just purchased a 2005 Blue Wave Classic Bay Boat with a Yamaha 2 Stoke 60. This is my first outboard boat. I bought the boat from auction and so I have no history other then it has 40 hrs on the motor and everything works great. The prop on the boat is a polished stainless steel 13 1/2 x 15 x 3. It has a hard time planing with two adults on board with a full tank and tackle. Once on plane, it will not rev past 2600 rpm fully trimmed etc. Does this prop sound like a wrong size prop? I dont believe it has a problem with the tach, as this is the original degital tach installed by the manufacturer. The tach revs in neutral to 3000 rpm with a rev governor kicking in. Does any of this make sense? Any help would be greatly appreciated. Thank you,

[boats.net]

A 2 stroke 60 should turn between 4500-550 rpm's at full throttle. May be engine is not running right, or incorrect tach reading or way too large pitch prop on it.