2004 SR Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 11Get this manual
GENERAL INFORMATION PROPELLERS
PROPELLERS An outboard motor is designed to develop its rated power within specified engine speed rangeThe maximum rated power delivered by the J10 and J15 models are shown belowRecommended full throttle speed range J10 J15 45005500 rpm 54006000 rpm
If the standard propeller fails to meet the above requirement, use another pitch propeller to hold the engine speed within the range specified abovePropeller selection chart