Slow Speed - 20MPH, 4750RPM Yamaha 150

[Captain Gump]

I have a 2013 2275 RCW with Yamaha 150 and stainless steel prop. Most of the summer, I have been running around top speed of 32 MPH with around 5500 RPM. This past weekend, I had a little more weight on the boat, with a couple of heavier people. But I maxed out at 20 mph with a max RPM of 4750 RPM. I have less than 50 hours on this boat and motor. Any ideas?

 

[BulldogsCadillac]

I don't know the answers, but the first thing people will want to know is what prop you have on there. It will help them answer you. They also will ask if your toons are clean, and what toon layout you have (twin elliptical, 3 toons, express package ) it will help the all knowing ones answer your questions, good luck!

 

[cwag911]

Yup, what prop do you have on there?

 

[Captain Gump]

I don't know the answers, but the first thing people will want to know is what prop you have on there. It will help them answer you. They also will ask if your toons are clean, and what toon layout you have (twin elliptical, 3 toons, express package ) it will help the all knowing ones answer your questions, good luck!

Derrick:

I have 3-Toon Elliptical Performance Package. Not sure about the prop, but dealer said it was "top-of-line" stainless steel prop. I will look up the specs on it. The boat does stay in the water, so you may have hit the problem when asking if my "toons are clean". However, I cannot believe that toons would get so much buildup in just a couple of weeks to drop my RPM from 5500 down to 4750.

 

[Captain Gump]

I have not changed the prop, so I am not really sure how that would factor into the question. I was getting 32MPH with 5500RPM, and it has dropped this past weekend to 20MPH and 4750RPM. No changes to the prop have been made, so I would not think that is a variable factor.

Was just curious, other than algae buildup on the Toons over a couple to three weeks, what else should I look at?

 

[Geoffrey & Brenda]

Have you tried it with just your normal load for comparison?

Your current prop sounds a bit low on max rpm, and may seem ok for your normal conditions, but once loaded, performance drops off. So propping correctly can make a huge difference.

Look in the 'props and power' section and see what others with a similar setup are running.

 

[floves]

I have a 2012 2275 RCW with the ESP package with a Yamaha 150 so other than the year the same boat. I normally get 32-33 mph at 5400 -5500 rpm's but my lake is large and normally has strong wind and lake chop.

Yesterday the lake was calm and very little wind. I recorded 38.4 on Garmin GPS and 38 plus on speedometer at 5800 rpm's. Nice to know that speedometer is right on. I'm sure you have a Yamaha Reliance stainless prop 14 1/2 x 15 Pitch. It will be clearly marked on the prop if you do.

Test reports on a boat very similar to ours shows the prop I mention with a top speed of 37.6 at 5750 rpms. Very similar to my results. http://www.benningtonmarine.com/publications/uploaded_files/17/Yamaha-PERF-BUL-2275RLi-F150TXR-Aug-2009.pdf

I'm thinking that it could be a combination of the algae build up and the weight was much greater than your normal load. If just wind and lake chop cuts my speed by six mph and rpms by 400 I think it's possible what you are experiencing. My results from yesterday was just me on board and almost no gear with half tank of gas. I also don't have the large fuel tank that most ESP owners have. I will try next week to get some heavy people on my boat and see how much speed and rpms decrease.

I did a test ride this year on a 2550RCW with tower and a Yamaha F350 that went over 50 mph but once it had 5 people on board it had a top speed of 43 mph. Let us know what you find out.

 

[Wild and Free]

I have a 2012 2275 RCW with the ESP package with a Yamaha 150 so other than the year the same boat. I normally get 32-33 mph at 5400 -5500 rpm's but my lake is large and normally has strong wind and lake chop.

Yesterday the lake was calm and very little wind. I recorded 38.4 on Garmin GPS and 38 plus on speedometer at 5800 rpm's. Nice to know that speedometer is right on. I'm sure you have a Yamaha Reliance stainless prop 14 1/2 x 15 Pitch. It will be clearly marked on the prop if you do.

Test reports on a boat very similar to ours shows the prop I mention with a top speed of 37.6 at 5750 rpms. Very similar to my results. http://www.benningtonmarine.com/publications/uploaded_files/17/Yamaha-PERF-BUL-2275RLi-F150TXR-Aug-2009.pdf

I'm thinking that it could be a combination of the algae build up and the weight was much greater than your normal load. If just wind and lake chop cuts my speed by six mph and rpms by 400 I think it's possible what you are experiencing. My results from yesterday was just me on board and almost no gear with half tank of gas. I also don't have the large fuel tank that most ESP owners have. I will try next week to get some heavy people on my boat and see how much speed and rpms decrease.

I did a test ride this year on a 2550RCW with tower and a Yamaha F350 that went over 50 mph but once it had 5 people on board it had a top speed of 43 mph. Let us know what you find out.

I get the exact same results only I can't top 5750 rpms at 38 mph gps with the rig in my signature. Same boat setup prop and engine, I have the 59 gallon center tube fuel cell and in floor storage, my speed runs are calm waters and half tank of fuel or less and 2 people on board with bimini standing up but not deployed.