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Selecting a prop for BF75A

I look forward to the results.

I look forward to the results.

I usually mount the Hondas a little higher than normal on the Montauks due to the boat sitting deeper in the water because of the extra weight of the four stroke engine on the transom. We also move the battery/batteries up under the console to help balance the boat.
 
"yes, I agree, my battery is i

"yes, I agree, my battery is in the console. It will be middle of next week before the prop is in. I will let you know how it turns out. Thanks again for all your help. What is wrong with the yamaha forum on this site? I saw a guy complaining that know one ever answers questions there, I looked and it does kinda look that way, maybe Honda mechanics are just more helpful."
 
"Mike, I got the 13"x13&#3

"Mike, I got the 13"x13"prop today, she turned a solid 5800, occassionally hitting 5900 rpm's. I really slowed the boat down, I hate it. The 15"x 13.5" prop had it at 5300 rpm's and it performed much better. I have run the boat with the 19" slilletto for 13 years @ 5200 rpm WOT, and she seems fine. I had to turn 4200 just stay on plane, what do you think, thanks"
 
"It is hard to answer your que

"It is hard to answer your question...

The higher rpms are better for the engine but it is apparently not good for you..

Are these stainless props that you are trying?

Maybe a compromise of 13 3/4 or 14 x 13. What brand prop are you trying? Mercury? Powertech?
I am certainly no prop expert. It's frustrating for my boss, but I just keep changing props until I fine a good compromise between rpm and performance. It sometimes takes a long time and a lot of analysis. Fortunately, most are pretty straightforward.

Here is a website for Powertech props. This gets you directly to a video with Steve Powers about choosing the right prop. http://www.ptprop.com/content/view/37/51/

We have worked with Steve on those occasions when the standard props do not work. They make the OFX props for Honda for the larger motors. They will make every attempt to make a prop that works best for your boat and motor combination.

If you can get your prop shop to work with him, it may help you get to your rpm/prop nirvana.

He does allow exchanges if the prop does not work out, but there is a slight charge."
 
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The prop is a PowerTech SCD3P.13PH1150 runs 5800 rpm, the previous prop was also a new poertech 13x13.5, it turned 5300 rmp, I don't have the model number here, I can get it tomorrow. At any rate, I'm going to pull the intake and examine the carbs again, different people keep asking if I'm getting full throttle. With the throttle cam fully engaged I don't see how I wouldn't be, but perhaps I'm overlooking something. So I will examine it on the bench, thanks for your help."
 
"Mike
I installed a new tach,


"Mike
I installed a new tach, went back to the 15x13.5 prop and borrrowed a gps. It turned 5600 rpm @ 34 mph, good hole shot, I like it, am I in the ball park? what do you think, thanks"
 
"It would probably be better f

"It would probably be better for the motor to get the rpms up, but you are very close. If you are happy with the performance and the motor sounds good, have fun!

Prop sizing is a bunch of compromises and when you look back, the rpms are closer to where they should be than they ever had been on your previous boat.

As they say, fish or cut bait. It sounds like it is time to "go fish"!!!"
 
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