CONTINUOUSWAVE

Measuring speed by gps

I appreciate your help.
Gear ration is .48 it also says (12:25)

Im guessing that means 2 to 1 but Im not familiar the numbers.

Would compression have any thing to do with it?
What about it running on 2 cyl without me knowing? The engine does not sound rough

thanks again

Well I was wrong. Full throttle and trimed it is only turning 4800 rpm not 5800 as i reported earlier
I was doing 35 mph

Any more help is appreciated

Q1: what prop do you have on the boat? The propeller [previously described as having unspecified number of blades and diameter 13.5-inch and pitch 18] is an Evinrude Raker 394758. Q3: is your tach functioning properly? By the sound of the motor I can't imagine it running at any higher RPM than indi...

My 1986 SUPER SPORT 15 has an Evinrude 70-HP engine with a stainless steel propeller [of unspecified number of blades] of 13.5-inch diameter and 18-pitch. [The engine can accelerate to a speed of] 6,000-RPM, but I seldom operate at that throttle because "the book" recommends (I think) to r...