What's safe rpm to cruise at?

[Nwextreme]

So having after having the boat for a Couple months now just going on on lake Washington Wakeboarding and hanging out never had the need or the conditions to open it up. We went camping last weekend and put it on on the columbia river which Is pretty calm, we headed upriver everyday to hit the sandbar where everybody hangs out which is a 20-30 m boat ride depending how fast you go. What's. safe rpm/speed to keep the boat running at for that kind of distance. I have the monsoon 340hp engine. I typically was keeping it between 35-43mph rpms between 3700-4400. Can the boat Handel more of a load than that or was that plenty?

[WakingMeHappy]

Wide Open Throttle!

[mnhays]

how much gas do you want to use is the question. gas vs time.

[Falko]

Long durations, I try not to go above 3800 or so. I am a baby...

[BlackBluMalibu]

Long durations, I try not to go above 3800 or so. I am a baby...

I agree with Falko... I think you should keep throttle around 75% or around 3800-3900 rpm, but even then vary somewhat on long hauls like that. Should give you 35-39 mph depending on your prop. Boat engines are like plane engines, they are designed to cruise at higher rpm but even still baby it so it will last you a lifetime! Good luck an have fun!

[MountainRob]

I like to keep it under 4k RPM for any extended periods. There is no doubt that higher RPMs puts more strain on many components.

[Fman]

4k tops for me when cruising....which is about 30 mph with acme 2315 prop.

[Timmay]

I agree with Falko... I think you should keep throttle around 75% or around 3800-3900 rpm, but even then vary somewhat on long hauls like that. Should give you 35-39 mph depending on your prop. Boat engines are like plane engines, they are designed to cruise at higher rpm but even still baby it so it will last you a lifetime! Good luck an have fun!

Actually, your motor is more like a Chevy truck engine than a plane engine. I cruise around between 2500-3000rpm. Having said that I don't think cruising at near 4000rpm is going to do any damage at all but you sure are eating a lot of gas doing that.

[KentC]

4k tops for me when cruising....which is about 30 mph with acme 2315 prop

I agree, feels plenty fast to me!!

[Levi900RR]

I messed around with my boat a few nights ago on my 10 min ride home from the sand bar...

WOT - 4900 RPM's = 44-45MPH

3900 RPM's was about like 39 MPH

3200 was about 36MPH.

I decided that about 3200 was my most efficient RPM's boat feels smooth and relativity quiet, and I still make decent time.

[wakedncsu]

I messed around with my boat a few nights ago on my 10 min ride home from the sand bar...

WOT - 4900 RPM's = 44-45MPH

3900 RPM's was about like 39 MPH

3200 was about 36MPH.

I decided that about 3200 was my most efficient RPM's boat feels smooth and relativity quiet, and I still make decent time.

what prop?

[JustinOSU]

We wakeboard with full ballast and wedge around 3500 rpm and sometimes a rider won't fall from 20 to 30 minutes. So I would have no problem cruising at 4000 rpm for 30 minutes.

Acme 537

[teamerickson]

We wakeboard with full ballast and wedge around 3500 rpm and sometimes a rider won't fall from 20 to 30 minutes. So I would have no problem cruising at 4000 rpm for 30 minutes.

Acme 537

If riders go that long without falling they are not pushing themselves enough.

[NCVride]

Why waste the gas? I Typically cruise around 26mph. Think that equates to around 2800-3000 rpms. Running 800-1000 more RPMs to only run 8-10 mph more isn't worth the wear and tear or the gas in my opinion. Think about how much more gas your truck burns turning 1000 more rpms. Why rush at the lake when your just going to hang out? Enjoy your time on the boat. The sandbar will be there when you get there. The only time I run 35 or more is pulling someone on a stick or trying to outrun a thunderstorm.

Edited July 23, 2013 by NCVride

[UWSkier]

I messed around with my boat a few nights ago on my 10 min ride home from the sand bar...

WOT - 4900 RPM's = 44-45MPH

3900 RPM's was about like 39 MPH

3200 was about 36MPH.

I decided that about 3200 was my most efficient RPM's boat feels smooth and relativity quiet, and I still make decent time.

Methinks your speedo is out of whack. With the 381 which is a 17.5, you should pretty much be 1:1 at slalom speeds. 3650 is 36 MPH on ours with the 381.

[Bill_AirJunky]

With 900 lbs of ballast, 26 mph is around 3250 RPMs on my Vride...... which is the speed I ride all the time. I don't see any issues running faster than that, but at some point your sucking a lot of gas to get there in a hurry. Just depends on how fast I need to be there. I usually cruise around 30 - 35 mph if the water is flat. And occasionally I'll open it up to see what it does..... just because.

Edited July 23, 2013 by Bill_AirJunky

[Nwextreme]

Thanks for all the input guys. I think I'll try to keep it at the 4k mark then. Like I said, I don't have the oppurtunity to open it up very often so when the oppurtunity arises, I don't mind spending the extra $20 it may cost me to have some fun. that's a fraction of the cost it take to maintain the boat for a season and I would rather fully enjoy what the boat can offer me than be cheap with it as long as I'm not causing any harm to the boat that's gonna cost me big on the back end. Like anything else you drive speed is always fun especially when you not breaking any laws and not having to worry about the popo.

[ToeCutter]

From I read it's meant to be run at Wide Open Throttle, and running at lower revs risks stressing the engine. My missus doesn't like using our prop which runs at 4k rpm for wakeboarding, preferring instead the prop which runs about 3k revs which sounds a lot calmer. I've been wondering which is most appropriate to use.