Prop ?? for the experts - Yamaha T50 / Dual Thrust vs Standard OEM prop performance

[606WPD]

I have a Yamaha T50 on my 22ft pontoon. The motor came with a standard 14X11X3 Yamaha OEM prop. Owners manual says that the WOT rpm range should be between 5000 and 6000. With this prop I was getting between 18 and 20 mph (GPS) at 5700 RPM.

I recently purchased a new Yamaha "Dual Thrust" prop, also a 14X11X3. This prop produces the same speed but only 5400 rpm - WOT.

I'm assuming the difference in rpm is due to the "Dual Thrust" design and the difference in blade shape and surface.

Is the motor designed to operate well anywhere within the 5-6000 rpm range?

Is the reduction in WOT rpm causing the motor to overwork?

Is there any way to increase rpm with the "Dual Thrust" prop?

For some reason I feel I'm leaving performance on the table by not utilizing the upper end of the recommended rpm range.

What say the experts?

Thanks

 

[Sea Rider]

Yep, the engine was designed to operate between 5-6 K wot rpm, is your current wot and speed while running lightly, medium or heavily loaded ? that's key to know as weight, hull shape, HP and wot rpm works as a team. You can always maximize a prop to suit your given load and application, you can get slight more rpm and end speed if well trimmed, weight is evenly distributed on deck and engine sits at the sweet engine/transom height.

Happy Boating

 

[606WPD]

Thanks Sea Rider. I would say it is loaded "medium." Full tank of gas and 500 passenger lbs, and another hundred pounds or so of "junk."

I'm satisfied with the performance I'm getting, I just wanted to make sure the engine wasn't lugging and I didn't want to leave anything on the table if I didn't have to.

 

[Sea Rider]

At that given medium load if say add one more non skinny passenger wot revs will decrease probably to near low wot rpm range. If for instance one or more boaters are left at Terra Firme wot rpm will increase accordingly. Engines likes being run at medium to full wot rpm range while at full throttle at any given load. That doesn't mean that you can't run engine at any desired non wot operating range as to maintain full plane.

Happy Boating