Got speed but rpm seems off

[jpertile]

New to me 2019 SSRXP w/ Yamaha F200, solas new Saturn 14.25x17p stainless prop.

Was out on lake after I bought it and gps indicated 38mph but rpm’s only showed 4800-5000.

That to me doesn’t seem right and thinking maybe the round rpm gauge is off. Engine runs great, sounds normal, no hiccups, stuttering or lags.

Will be hooking engine to my hds via NMEA 2000 this winter to verify actual engine rpm’s before I dive down the rabbit hole of repropping. See where a lot are running a 14.5x15p stainless with this engine.

Wanted to gauge y’all’s view of rpm’s versus gps speed that I am seeing.

I know manual for f200 says wot is 5000-6000 but I believe I should be closer to the 6000 being Yamaha says it takes 5500 to produce the 200HP.

 

[Vikingstaff]

I am not a fan of the Solas prop for your motor if going for good performance. And 17p is WAY TOO MUCH for that motor. Your gage seems correct for how you are proped.

You should be as close to 6000rpms as possible with a light load. If dialed with a good SS prop you will be around that rpm wise, and likely somewhere around 42-44 mph at WOT depending on how big your boat is (are you somewhere around 22-25’ long?)

Personally I would go with SS Enertia 15p or SWSII 15p for that f200. Not all SS props are the same. Cupping and what not can really impact performance, efficiency, etc… greatly. And honestly no need to hook up and do diagnistocs on that gauge. Your RPM’s align with how over-sized your prop pitch is for that motor. All your number seem fairly spot on for the prop you are using now.

Time to go down that rabbit hole…

That said, CONGRATULATIONS on the boat. Exciting!!! Share pictures if willing. We love looking at everyone’s newer boats. How’s the rest of it so far? Liking it?

 

[jpertile]

I am not a fan of the Solas prop for your motor if going for good performance. And 17p is WAY TOO MUCH for that motor. Your gage seems correct for how you are proped.

You should be as close to 6000rpms as possible with a light load. If dialed with a good SS prop you will be around that rpm wise, and likely somewhere around 42-44 mph at WOT depending on how big your boat is (are you somewhere around 22-25’ long?)

Personally I would go with SS Enertia 15p or SWSII 15p for that f200. Not all SS props are the same. Cupping and what not can really impact performance, efficiency, etc… greatly. And honestly no need to hook up and do diagnistocs on that gauge. Your RPM’s align with how over-sized your prop pitch is for that motor. All your number seem fairly spot on for the prop you are using now.

Time to go down that rabbit hole…

That said, CONGRATULATIONS on the boat. Exciting!!! Share pictures if willing. We love looking at everyone’s newer boats. How’s the rest of it so far? Liking it?

Yes it is a 22ft tritoon with sps. Picked it up about a month ago. Love the ride it has, came from a 20ft deck boat, this Benny rides like a dream!!! Had a couple things I found wrong, called a local dealer and got everything covered thru warranty so that was awesome. And got a lot of stuff planned for over the winter break. Alabama winter so will be back in water come march.

 

[SEMPERFI8387]

Nice ride and love your co-pilot!

 

[Julianna]

Nice looking ride! Congrats

 

[Toddk9]

FYI - This guy has videos on setting up the Garmin Striker 4 on your boat. I learned a lot from him and now enjoy the little unit. He has many classes for it. I watched class 2-4

 

[Compromise2]

I worked with Prop Gods, as have others.
We gave him boat and motor specs, he gave us recommendation and got it right on first try.

Also, if performance is still not as you hoped, he exchanges for small fee and you try a different set up.

 

[Potomacbassin’]

Looks reasonable to me. A 17p prop with that 1.86 gearcase would theoretically travel 43 mph at 5000rpm with zero slip. With your 38mph that's a 12% slip which is in range IMO for a lighter tritoon.

What speed were expecting at that RPM?

 

[jpertile]

Looks reasonable to me. A 17p prop with that 1.86 gearcase would theoretically travel 43 mph at 5000rpm with zero slip. With your 38mph that's a 12% slip which is in range IMO for a lighter tritoon.

What speed were expecting at that RPM?

Wasn’t sure what to expect as far as speed since we bought it late in the season and only had it out a couple of times. I was more concerned to the fact that when I went W.O.T. I could only get to 5000 rpm’s on a motor that should get to 6000 when testing wot and according to Yamaha doesn’t reach full 200hp until 5500. All of which started me questioning my tachometer and/or current prop pitch. New to Bennington tritoon so wasn’t sure what to expect speed wise or if considered a light pontoon or what not.

 

[jpertile]

FYI - This guy has videos on setting up the Garmin Striker 4 on your boat. I learned a lot from him and now enjoy the little unit. He has many classes for it. I watched class 2-4

Yes I have watched those as well. I just don’t like how the map is so basic, doesn’t show contours etc and looking to connect my engine to something which you can’t do with the striker 4 but will leave it installed on the boat.

 

[Potomacbassin’]

Wasn’t sure what to expect as far as speed since we bought it late in the season and only had it out a couple of times. I was more concerned to the fact that when I went W.O.T. I could only get to 5000 rpm’s on a motor that should get to 6000 when testing wot and according to Yamaha doesn’t reach full 200hp until 5500. All of which started me questioning my tachometer and/or current prop pitch. New to Bennington tritoon so wasn’t sure what to expect speed wise or if considered a light pontoon or what not.

I gotcha, didn't realize 5000 was WOT rpm.

A couple things:

1) make sure everything is as designed and spec'd i.e. engine is running properly, proper fuel (Yamaha recommends 89 for the F200?) trim and clean toons etc

2) do you have the wave tamer under skinning? That can knock off quite a few mph and rpm

3) looks like you are in the lowest mounting hole for your OB, raising one or two holes will pick up both speed and RPM, probably on the order of 200-300RPM

4) I don't know much about the Solas Saturn but it might be too much prop at 17p for your inline 4 as Viking noted - a Yamaha Reliance 17p might be a better match, or if Solas makes a 16p?

5) I would see what Ken at Propgods says

6) I wouldn't hook your engine up to your Lowrance unless you have a spare N2K backbone laying around. If you just want to get engine revolutions your dealer might be able to hook up the diagnostic cpu into your ECM and see, or buy one of those chintzy portable tachs that coil wire around the spark plug wires