Honda BF5 Prop Pitch

[Dougo]

I'm running a Honda 5hp 4-stroke with the stock prop (7 1/2 pitch) on my h23. Toying with the idea of going to the lower pitch available (6 5/8) help get a bit more response from the motor (especially reverse). Can anyone out there who's made the switch tell me if it's worth the expense. Props are a bit pricey, but I'm willing to spring for it if it's worth it. Does it make that big a difference?

Thanks
Doug

 

[anchorclanker]

You really need to read a tachometer before you start playing with props. Lower pitch will allow the engine to rev higher, and if it over revs high enough it will damage it. OTOH, going to higher pitch can overload the engine to the point it cant rev into its power range and it will live a shorter life, burning extra fuel.

That particular engine has a full throttle RPM range of between 4500 and 5000 RPM, meaning you want the engine somewhere between those two numbers at full throttle.

 

[Erieau]

Just yesterday, I changed out the prop on my BF15 from the stock 3-blade 9.5 X 8 5/8 to a Solas 4-blade 5 X 10. Being used to running just above idle, I was a little unnerved to hear the motor running so fast. Below in the cabin, my wife said it actually sounded much smoother running at higher RPMs.
The best part of the switch is that shifting gears isn't such high drama anymore. It calmly ka-chunks into forward gear and then smoothly accelerates away, instead of leaping into the air and bogging down to the point of stalling.
For me, it was worth the 90 bux.

 

[FourPoints]

Go with the new 4 blades, they also have an oversized hub to allow exhaust gas to exit forward through the hub while in reverse so you aren't spinning the prop in the bubbles.

I just put one on this year, and WOW! What a difference it makes, it's like I added 40% more engine power than I had with the old 3 blade.

 

[Dougo]

Go with the new 4 blades, they also have an oversized hub to allow exhaust gas to exit forward through the hub while in reverse so you aren't spinning the prop in the bubbles.

I just put one on this year, and WOW! What a difference it makes, it's like I added 40% more engine power than I had with the old 3 blade.

Any suggestions as to where to find a 4 blade prop? The Honda low pitch model is 3 blade.

 

[tkanzler]

I don't think that BF5 has through-hub exhaust. I would think prop choices would be pretty limited, too.

 

[FourPoints]

I got mine from boats.net, easily the best $70 I have spent on the boat since the day I bought it.