Which Prop for New 23RSR with Yamaha F300XCA

[sunnyside360]

Picked up my new 2018 Bennington 23RSR with Yamaha F300 XCA outboard on Saturday 10/7/2017. Most options are shown in signature. Currently going thru the specified break-in process with dealer installed Yamaha Salt Water Series II prop with 16 inch pitch. Put the hammer down briefly with 2.8 hrs on the meter and recorded the data below. This was with two adults, full tank gas (54+ gal), and approx 50 lbs gear. Speed data was taken using factory Garmin GPS.

2000 rpm 9.66 mph
3000 rpm 19.7 mph
4000 rpm 28.4 mph
5000 rpm 38.2 mph
5900 rpm(wot) 44.8 mph

I thought WOT would be more like the performance test data on Yamaha website, i.e., 47.3 mph at 6000 rpm for near identical boat and motor.

The boat is used for water skiing, tubing and cruising usually with 6 to 8 people on board (teen age grand kids).

Looking for some critique on the above data along with advice on propping. Thanks.

 

[Jb75]

First congrats on a great boat. Looks to me if you are trimmed properly at wot you are probably pretty close to perfect at that mounting height. You would be able to squeeze more speed with a higher pitch but will lose acceleration. Moving the motor up one hole will get you even more top end but may increase your chances of ventilation when cornering. I'd possibly consider a 15 1/2x17 pitch.

 

[Jb75]

I've tried a 151/4x18 and 151/2x16 on my 2250 gsr(smaller and lighter than yours) with a 250 yammie. The 18 ran around 46.5-47 at 5400. it wasn't very weight sensitive. (I.e. That was topend whether loaded up or empty). The 16 is more sensitive to weight. Loaded at max capacity I can muster 40 and empty (just me and 15gals) 48.4 at 6100. I like the 16 better for our uses. Better low end punch for towing water sports. Seems to be about a 45 mph boat at lowest
Mounting and typical load. 4 adults, 2 kids, Labrador and a big yeti. I have a 17 pitch I'll throw on soon just to see how it does.

 

[cwag911]

You should really wait until you've finished the break in to start shopping for props.

 

[Alicedream]

I have 2017 RCW with a Yamaha 300 XCA and have Saltwater II 17 pitch. My top end ranges between 46 to 49 depending on conditions. Keep in mind once you get to 45 you have to trim 3/4 to get to top end. My motor is also in the 2nd hole from the top.

 

[sunnyside360]

First congrats on a great boat. Looks to me if you are trimmed properly at wot you are probably pretty close to perfect at that mounting height. You would be able to squeeze more speed with a higher pitch but will lose acceleration. Moving the motor up one hole will get you even more top end but may increase your chances of ventilation when cornering. I'd possibly consider a 15 1/2x17 pitch.

The motor is mounted in hole #1, lowest position the motor can be mounted. Readings were all taken at 1/4 motor trim. I didn't experience any prop ventilation yet but didn't do much turning at higher speeds. Will do some more testing after break-in. These props are ultra expensive but hopefully the dealer will be willing to try a different prop. Thanks.

 

[sunnyside360]

You should really wait until you've finished the break in to start shopping for props.

Agree with you 100%. I am just looking for advice on propping for this setup for best all around performance. I know more testing needs to be done. Thanks.

 

[sunnyside360]

I have 2017 RCW with a Yamaha 300 XCA and have Saltwater II 17 pitch. My top end ranges between 46 to 49 depending on conditions. Keep in mind once you get to 45 you have to trim 3/4 to get to top end. My motor is also in the 2nd hole from the top.

Great, near identical boat as mine. The dealer considered both 16 and 17 inch props and wound up installing the 16 inch prop (Bennington recommendation). The motor is mounted in hole #1 (lowest setting) and the trim was set at 1/4 for all above test data. I'll vary the trim as you suggested after the break-in.

Do you use regular, mid, or high octane gas? My manual specifies mid (89 octane). Straight 89 octane is very hard to find in central PA. I know some folks use higher octane 91 or 93, and some use lower octane 87 all of which are easier to find. Thanks.

 

[cwag911]

Do you use regular, mid, or high octane gas? My manual specifies mid (89 octane). Straight 89 octane is very hard to find in central PA. I know some folks use higher octane 91 or 93, and some use lower octane 87 all of which are easier to find. Thanks.

Always go higher. Our new 2017 Explorer will run on 87 but likes 93 octane much better, much more power.

 

[Jb75]

im guessing based off my boat you have quite a way to go with the trim. my guess is you will get the extra 100 rpm and extra speed with trim between 1/2 to 3/4. the 16 may be just right in that mounting location.

The motor is mounted in hole #1, lowest position the motor can be mounted. Readings were all taken at 1/4 motor trim. I didn't experience any prop ventilation yet but didn't do much turning at higher speeds. Will do some more testing after break-in. These props are ultra expensive but hopefully the dealer will be willing to try a different prop. Thanks.

 

[sunnyside360]

Always go higher. Our new 2017 Explorer will run on 87 but likes 93 octane much better, much more power.

Good. I will try 93 octane when I fill.

 

[sunnyside360]

im guessing based off my boat you have quite a way to go with the trim. my guess is you will get the extra 100 rpm and extra speed with trim between 1/2 to 3/4. the 16 may be just right in that mounting location.

Little better performance would be great if more trim will help with the 16" prop.
My last Bennington (2014 RL, ESP) with Evinrude 225HO and 17" pitch prop had great hole shot and top speed of 46.6 mph with light load. I'm hoping this boat will at least equal that. Could not trim Evinrude 225HO past 1/4 w/o issues. However, good all around performance and economy are important to me which means getting the right prop. Thanks.

 

[Alicedream]

Great, near identical boat as mine. The dealer considered both 16 and 17 inch props and wound up installing the 16 inch prop (Bennington recommendation). The motor is mounted in hole #1 (lowest setting) and the trim was set at 1/4 for all above test data. I'll vary the trim as you suggested after the break-in.

Do you use regular, mid, or high octane gas? My manual specifies mid (89 octane). Straight 89 octane is very hard to find in central PA. I know some folks use higher octane 91 or 93, and some use lower octane 87 all of which are easier to find. Thanks.

I use 91 octane all the time and occasionally have used 93 octane.

 

[sunnyside360]

Just for grins, I found this Prop Slip Calculator http://www.go-fast.com//Prop_Slip_Calculator.htm and determined my prop slip is 12%. That is with 44.8 mph actual speed, 5900 engine rpms and 1.75 gear ratio. Speed with zero slip is 51 mph. I calculated prop slip for a few others with test data on Yamaha website and found they run around 7% to 8% with light loads. At 7-8% slip, my actual speed should be 47 mph. Suspect trim and motor mounting height are major contributors to the difference between 12% and 7/8% prop slip. Can't wait to get out again to complete the break-in process and do some more testing with the trim.

 

[sunnyside360]

With over 6 hours on the meter, did some testing with the trim over the weekend with the new 2018 23RSR and 16" prop. At 1/2 trim, speed maxed out at 46.2 mph @ 6000 rpm with 2 adults and full tank gas (54 gal). It was a bit windy, choppy water, and 72 deg F. That comes out to be 11% prop slip which seems a little high.

Then tried with 3/4 trim and boat started porpoising slightly above 1/2 trim so don't think I can trim any more than 1/2.

Now thinking about trying the 17" pitch prop but it will have to be next spring since the boat has been put up for the winter. Anyone have any insight on the 17" prop?

 

[goldnrod24]

Now thinking about trying the 17" pitch prop but it will have to be next spring since the boat has been put up for the winter. Anyone have any insight on the 17" prop?

What is the max recommended rpm for your motor? I seem to remember each =/- inch of pitch = +/- 200 rpm, so knowing your max rpm is important.

 

[Jb75]

I'm also around 11% slip. Will put on a 151/2x17 soon and let you know how it runs. It is a new Solas Lexor which does not appear to be the same quality as the swsII but for 260 I thought it would be good to try. if I decide I like the 17 I thought I would have my yammie prop blueprinted and worked to a 17 at lake Lanier propeller. May be possible to add some cupping to decrease slip as well????

 

[Alicedream]

With over 6 hours on the meter, did some testing with the trim over the weekend with the new 2018 23RSR and 16" prop. At 1/2 trim, speed maxed out at 46.2 mph @ 6000 rpm with 2 adults and full tank gas (54 gal). It was a bit windy, choppy water, and 72 deg F. That comes out to be 11% prop slip which seems a little high.

Then tried with 3/4 trim and boat started porpoising slightly above 1/2 trim so don't think I can trim any more than 1/2.

Now thinking about trying the 17" pitch prop but it will have to be next spring since the boat has been put up for the winter. Anyone have any insight on the 17" prop?

I have the 15.5-17 Saltwater II and I can trim above 1/2to just under 3/4 with no porpoising. My top end is usually in the 46 to 48 window.Again, I am in the second hole. I am sure if I wanted to play with engine height and other props I might get a little more top end. My RPM at top end is usually around 5800 and occasionally 5900. I just don’t think it is worth it to play around for maybe 1 mph.

 

[sunnyside360]

What is the max recommended rpm for your motor? I seem to remember each =/- inch of pitch = +/- 200 rpm, so knowing your max rpm is important.

Yamaha specs indicate operating range of 5000 to 6000 rpm. Mine gets to 6000 rpm fairly quick. Thanks.

 

[sunnyside360]

I'm also around 11% slip. Will put on a 151/2x17 soon and let you know how it runs. It is a new Solas Lexor which does not appear to be the same quality as the swsII but for 260 I thought it would be good to try. if I decide I like the 17 I thought I would have my yammie prop blueprinted and worked to a 17 at lake Lanier propeller. May be possible to add some cupping to decrease slip as well????

Will be interesting to see how your 17" performs. Good idea about the cupping. Thanks.