Solas Amita 4 Blade Prop Performance and a Question

[Mooch]

Finally got around to putting a 4 blade prop on my Honda BF150 and thought I'd share my initial results:

Solas Amita AL 14.75 X 15 4 Blade
RPM   MPH   
1000   3.5
2000   4
2500   6
3000   9  Plane  ~ 12 sec
3500   14
4000   20
4500   22  Sweet Range
5000   29  Sweet Range
5500   32  Sweet Range
6000   36 WOT

My previous prop was:

PowerTech SS 14.25 X 17 3 Blade
RPM   MPH
1000   4
1500   7
2000   8
2500   9  Plane ~17 sec
3000   11
3500   20  Sweet Range
4000   25  Sweet Range
4500   30  Sweet Range
5000   33
5500   36  WOT
6000   MA

My PowerTech SS 3 blade 14.25 X 17 is very smooth through the mid range and has a very comfortable low RPM sweet spot between 3500 (22 MPH) - 4500 (28 MPH) heavily loaded and is wonderful cruising Puget Sound and bays.  It also performs remarkably well trolling and backtrolling at low speed.  However, on the ocean I'm willing to give up speed and smoothness for quicker hole shot and greater overall responsiveness in varied conditions.  More often out there I'm wishing I could drop down a gear.  The Solas Amita 4 blade certainly did that and more.  Not only did I pick up an extra 500 RPM at WOT (520 to be precise at 6020 - Hope that's OK on rated range of 5-6K) but I also picked up ~5 sec on my hole shot.  What I also found was it ran very strong the upper RPMs.  Mid range definitely not as smooth or comfortable as the PT.  Also something I was not expecting was how much it raised the bow on acceleration compared to the PT with engine trim down.  Definitely a noiser running prop than the PT IMO, which brings me to a question about a noticeable whirring sound I hear somewhere above idle in the steady 1000-2000 RPM range (mid-fast troll, not acceleration).  I've attached a video that might help someone identify it.  I've never heard this before so hoping someone might know more about it.  Not worried, just curious if anyone else has heard this.  Thanks.

https://www.youtube.com/watch?v=IBl5xNbSniA

[Fisherdv]

I also have a PowerTech SS SCD-3, 14p, and a Honda Solis 4-blade 13p. There is definitely a different engine sound to them especially in the low, to cruise range. Granted I only have a 60HP Honda motor.

The sound difference may be from the varying drag on the motor and different pitch.

I would say it's normal, but if you think it sounds way off, then look into it a bit further.

[ATGEP]

I have run the same solas 4 blade for the past 4 years.  Overall I am 90% happy with it.  Likes: Torque and low to mid speed performance.  Dislikes: lack of top end speed and excessive stern lift.  90% of the time I am very pleased. When the water is glassy "10%" of the time I dream of a higher top speed.