How many RPM's is too many for cruise

[TxHorns]

I know the right answer to this question is "depends", but just generally speaking, is cruising around 4400 RPM's considered running your engine hard?

I usually try to stay around 4000-4200, but one of my motors is having trouble holding RPM's in that range and I'm constantly staying on the throttle.

Thanks for the input. Motor is 1992 Johnson 140.

 

[Sixmark]

Re: How many RPM's is too many for cruise

I try to keep my cruising speed at the lower end of the WOT envelope, if you are adjusting your speed because one motor can't keep up then the answer isn't lowering your cruising RPM's. The answer would be to find out why the second motor isn't holding RPM.

 

[Silvertip]

Re: How many RPM's is too many for cruise

Cruise means different things to different people and will vary from boat to boat because of the amount of power available. Cruise to most people would be from just on plane to anything short of wide open throttle. Only you can determine what "cruise" is for you, your boat, and your load. Being underpropped can require throttle settings that are way higher than they would need to be if propped correctly so cruise RPM is sort of a non-factor.

 

[keefallan]

Re: How many RPM's is too many for cruise

I agree with SIXMARK. I would figure out why your other motor won't hold it's rpm's at the setting you choose. It sounds like you can get it to hold at 4400but its difficult a little lower. Why???? I personally wouldn't cruise that high. Fuel economy drops off very quickly the higher you go above 4000-4200(typically)

 

[surrender]

Re: How many RPM's is too many for cruise

My 88 Special WOT range is 5600-5800 so I like to cruise at 4800. May burn more fuel but am I really? If I drop to 4200-4400 as some suggest I lose over 7 MPH. Doesnt really matter to me, boat really is pretty good on fuel for a 14 year old 2 stroke!

 

[TxHorns]

Re: How many RPM's is too many for cruise

yeah, I know I should get it checked out. But I just haven't been able to get it to the shop yet and I also just put some money into it not long ago. To be honest, on that same motor, my tach cuts in and out (first thing to fix), and I'm not certain that its getting the right reading.

I guess I was just wondering if (assuming everything was working just fine) you guys would consider 4500 rpm's to high to run your boat for regular driving. It sounds like maybe not.

Thanks for the input.