4500 max RPM on new 60hp

[biggreen60]

Any ideas on why my max RPM is 4500 after breakin period. Prop is a 10.25 x 14

part #6H5-45958-00-EL

boat is a 19' C-Dory that was powered by honda 45

getting decent speed but prop is actually smaller than what I had on the old 45HP honda.

Any advice is greatly appreciated

[boats.net]

If the tach is accurate and this is four stroke 60 then you would need to drop to a 9 pitch to gain about a 1000 rpm's.