No doubt these versatile power-sailors can easily exceed 20 knots with a 50 HP 4 stroke running flat out and a minimal load. My experience with 2 stroke outboards tells me they don’t last long when run continually at near max power settings. It would be very helpful to know what boat performance and engine life can be expected for different HP sizes and more typical payloads and lower power settings. Do any owners have some data on the cruising speed that can be can be expected at 3,500, 4,000 and 4,500 RPM with a 40, 50 and 60 HP engine for a payloads (people/fuel/stuff/etc.) of say 600 and 1000 lbs.?
Boat performance vs. engine usage and life
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fully loaded, 6 kts at 2800 rpm
I have a 2003 26M with a Honda 50 hp. With a full ballast tank, mast raised, center board and rudders down, and 3-4 people, she easily cruises at 6kts at an rpm of 2800. Again, with a full ballast tank, mast raised, 2 adults, center board and rudders raised, she'll hit about 13-14 kts at 5800 rpm. Hope this helps. Kirk
I have a 2003 26M with a Honda 50 hp. With a full ballast tank, mast raised, center board and rudders down, and 3-4 people, she easily cruises at 6kts at an rpm of 2800. Again, with a full ballast tank, mast raised, 2 adults, center board and rudders raised, she'll hit about 13-14 kts at 5800 rpm. Hope this helps. Kirk
Honda data
I took the following data from a now unknown website. It had a contact of jack@apmweb.com. The data was for a Honda 50 with 2 six gallon tanks: 3000rpm, 7mpg,7mph, fuel used in one hour - 1gal; 4000rpm, 5mpg, 9mph, fuel used in one hour - 1.8 gal; 5000rpm, 4mpg, 14mph, fuel used in one hour - 3.5 gal; 6000rpm, 3mpg, 15mph, fuel used in one hour - 5 gal. I hope my numbers are still correct and this info helps you. There was no reference to weight.
I took the following data from a now unknown website. It had a contact of jack@apmweb.com. The data was for a Honda 50 with 2 six gallon tanks: 3000rpm, 7mpg,7mph, fuel used in one hour - 1gal; 4000rpm, 5mpg, 9mph, fuel used in one hour - 1.8 gal; 5000rpm, 4mpg, 14mph, fuel used in one hour - 3.5 gal; 6000rpm, 3mpg, 15mph, fuel used in one hour - 5 gal. I hope my numbers are still correct and this info helps you. There was no reference to weight.
2 stroke performance
My experience with 2 strokes is that they run and run and run. And with minimal maintenance. I ran a 2 stroke 90 on a 17 ft ski boat for 18 years -- wide open for most of the time. Changed lower unit oil every yr and plugs about every 5 yrs. Water pump once. I ran a two stroke 35 on a 15 ft fishing boat for 15 years, sold it and it is still running 9 yrs later. Only maintenance, lower unit oil and plugs. I now have a 2 stroke 75 on a bass boat which is 29 (yes 29) years old. I run long distances wide open. The only maintenance other than lower unit oil and plugs was carb rebuild last yr. When I bought my 2001 26x 3 yrs ago, I put a 2 stroke 50 Merc on it. 2 stroke -- lighter, less expensive, less maintenance, proven reliability (at least to me) under demanding use. Does use more gas and is not allowed on some lakes. One of the most important keys to performance is to match the prop to "usual conditions". I experimented with at least 5 props before choosing a 3 blade 11 5/8 X 10. It gives me a little over 20 MPH @ 5500 (as determined by GPS)with empty tank and two on board. Fully loaded I can do 10 MPH @ 4000. I don't know what you mean by running continually, but 2 strokes have always worked for me under all conditions. In the end it is personal preference and experience.
My experience with 2 strokes is that they run and run and run. And with minimal maintenance. I ran a 2 stroke 90 on a 17 ft ski boat for 18 years -- wide open for most of the time. Changed lower unit oil every yr and plugs about every 5 yrs. Water pump once. I ran a two stroke 35 on a 15 ft fishing boat for 15 years, sold it and it is still running 9 yrs later. Only maintenance, lower unit oil and plugs. I now have a 2 stroke 75 on a bass boat which is 29 (yes 29) years old. I run long distances wide open. The only maintenance other than lower unit oil and plugs was carb rebuild last yr. When I bought my 2001 26x 3 yrs ago, I put a 2 stroke 50 Merc on it. 2 stroke -- lighter, less expensive, less maintenance, proven reliability (at least to me) under demanding use. Does use more gas and is not allowed on some lakes. One of the most important keys to performance is to match the prop to "usual conditions". I experimented with at least 5 props before choosing a 3 blade 11 5/8 X 10. It gives me a little over 20 MPH @ 5500 (as determined by GPS)with empty tank and two on board. Fully loaded I can do 10 MPH @ 4000. I don't know what you mean by running continually, but 2 strokes have always worked for me under all conditions. In the end it is personal preference and experience.
Suzuki
What type of a prop do You use? (Material - aluminium or stainless steel, diameter, pitch). I have a 2003 26M with a 4 stroke Suzuki 50 hp.I use aluminium 3 blade prop 11 1/2 X 14 now. It gives me a 12 MPH @ 4200 (determined by GPS)with empty tank and two on board. But I cannot reach the maximal RPM.
What type of a prop do You use? (Material - aluminium or stainless steel, diameter, pitch). I have a 2003 26M with a 4 stroke Suzuki 50 hp.I use aluminium 3 blade prop 11 1/2 X 14 now. It gives me a 12 MPH @ 4200 (determined by GPS)with empty tank and two on board. But I cannot reach the maximal RPM.
Prop material
I use an aluminum prop for my 26x -- 11 5/8 dia x 10 pitch. 14 pitch is probably too much as evidenced by not achieving maximum rpm. It is extremely important that the motor operate within its specified rpm range which, depending on manufacturer, is generally between 5,000 to 6,000. With the 10 pitch prop motor will do 5,700 rpm. If possible you should try several different props to determine optimum. If not, keep the 12 as a spare and get a 10 pitch. That is just my opinion. If you get the right size, stainless will probably give a little better performance than aluminum.
I use an aluminum prop for my 26x -- 11 5/8 dia x 10 pitch. 14 pitch is probably too much as evidenced by not achieving maximum rpm. It is extremely important that the motor operate within its specified rpm range which, depending on manufacturer, is generally between 5,000 to 6,000. With the 10 pitch prop motor will do 5,700 rpm. If possible you should try several different props to determine optimum. If not, keep the 12 as a spare and get a 10 pitch. That is just my opinion. If you get the right size, stainless will probably give a little better performance than aluminum.
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