craig wrote:I've never tried a larger motor on my Pocketship, so I can't speak to personal experience. And sure, larger motor = slower RPM for hull speed = less noise. Agreed all around. And obviously your boat, your call! haha. I guess in my opinion, I can't see the noise reduction being so large as to balance the MUCH heavier weight hanging off the transom (double in this case, from 30 to 60 pounds) and the resulting negative effect on weight distribution and sailing properties. Plus the possibility of a large cutout in the transom, which is a pretty dramatic change.
All to say, everyone has different priorities. I'm sure you already have done so, but my advice would be to think hard about whether more money, weight, and big alterations to the boat justify the lower noise. If you can get a noise reading on a small motor vs. larger motor at the RPM you will be running at, that's even better. I guess I've never heard a quiet outboard - they are all noisy.
Totally agree on the long shaft vs. short (15in). Mine is 15in and I wish I had the longer version (which wasn't available at the time I bought mine). Short shaft does work, although in big rollers your prop will partly come out of the water at the crest (still good for emergencies or short periods of time, though) . On lakes, quiet water, etc it is fine all the time.
Craig, I appreciate your comments. Yes, we all have different applications for our sailboats, which seems to drive our outcomes. My desire to use the Sailpro 6 is based more on the following issues than the sound. Sound may be a benefit but as you've noted, probably insignificant. I see the following as the benefits of the 6 hp Sailpro.
1-The availability of a 25" shaft. This will allow me to mount the motor with the skeg (the lowest part of the outboard) 1" above the bottom of the rudder while still being able to operate the controls. The extra length makes this possible. In this fashion, the rudder should hit ground before the outboard. Yet the outboard will be as deep as possible for a solid grab in the water. Remember, the lower you go, the denser the water. The negative will be that unless you take the time to shim the transom, the 25" long shaft may drag in the water when sailing. But, properly shimmed, I'm told the Sailpro does not drag in the water when heeled.
2-High thrust prop. The wide 8.375" diameter prop combined with the 6" pitch is designed to push heavy items at a slow rate. This is ideal for all day motoring up a narrow channel when exploring. You might be able to add this prop to a smaller engine, but it appears to be optimized with the 6 hp engine.
3-Lower RPM's. Based on actual users, the 6 hp allows you to reach hull speed at 1/3 throttle, with plenty in reserve for unexpected situations. This should prolong the life of the motor, be quieter and create less vibration, though the actual amounts might be insignificant.
4-A Reverse Gear. I've never quite gotten comfortable swinging the outboard 180 to reverse. I seem to throttle the wrong directions when timing matters most. If you can go the 6 hp engine, you get a reverse on the front of the motor for easy and quick gear changes with intuitive steering.
If weight were the same, I would for sure want these benefits. OK, but the weight isn't the same, so what about that extra 30 pounds? If you're willing to cut away the transom (and I know that's a big request), you get to subtract the outboard bracket weight because you will be mounting the outboard directly to the transom. Some claim the outboard brackets can weigh 20 lbs, I've never weighed one. I do know from personal experience, they are prone to vibrate (which creates more noise), and they're cumbersome and clunky. Hence, my decision to direct mount my outboard.
Also, if you're willing to cut away the transom, the motor mounts further forward, reducing the lever arm effect of said motor weight. Also, by cutting away the transom, you can sit further forward in your boat when operating the outboard. If you weigh 200 lbs like me, this is not insignificant. Also, the gas now resides in a small 2 or 3 gallon tank in the footwell (No, you don't have to fill it full). The visual tank eliminates range anxiety, but also moves yet more weight forward in the boat. And, finally, you can subtract the weight of the transom you removed. When you add all this up, I'm not convinced there exists much of an overall weight differential between a 2.5 hp 30 lbs outboard (mounted with a standard outboard bracket hanging off the back) and the 6 hp 60 lbs outboard (directly mounted to the transom).
At the end of the day, each sailor needs to choose whatever he is most comfortable with and go with that system. I'm confident both approaches probably work acceptably well in most situations.