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My surveyor recommended I figure whether I'm getting good speed out of my motor.

With 4 people and a full ballast, we topped out at 8.8 knots. Is that good? He claimed with fewer people and an empty ballast she should do about 14.

I have an ETEC 60 so I really can't say but may I suggest you include the year and model of your boat?

I routinely get about 15-16 knots at 4500 rpm on my 26M with my Honda 50. That is with the ballast dumped though. I have not ever tried getting up on plane with the ballast in.

I have a 50 HP Johnson, and it tops out at about 12 kts with full ballast and 2 people. With just myself & full ballast, about 13 kts. I haven't tried without ballast, since that is not a wise idea on SFO bay.

Roger

David Mellon wrote:... include the year and model of your boat?

Right.

2001 X

26M, Yamaha 5o, 500lb of humans, no mast and no ballast I got 17 knots.

We get 12-14 knots loaded with 4 adults with a 2002 Honda 50. What prop do you have installed?

I have an "05" , powered by a Honda 50 four stroke, and I get up to 14 MPH (12.1 knots) with four people and the ballast full. With an empty boat (and I mean stripped down), empty ballast, and just me, I have been up to 19 MPH.

I don't believe a 50 can get a Mac on plane. I think you have to going over twenty MPH (16.5 knots), and at that speed, you will also be getting very wet from the spray.

Ray

Dave,

With a 50 horse you should be able to get at least 11 or 12 mph. I would venture a guess that the current owner does not have the engined propped properly. Most standard props (often provided with the engine) are geared too tall to push a boat as large as a Mac. Find out what pitch the current prop is and what the maximum rpms are that you are getting. The engine manual should list a desired rpm range the motor wishes to max out at. Given the same diameter prop every inch less pitch should give you about 200rpm more.

Keep asking questions here. By the sound of your posts it looks like the current owner of the Mac never got it dialed in properly.

Theo

Concur with the wrong prop thesis. Find out what the Honda 50's ideal RPM under wide open throttle is supposed to be, and then determine what your prop is doing by going WOT and recording your RPMs. If you aren't in or near that ideal range, you need to change the prop. There are a number of prop pitch calculators online you can use to get a good idea what your properly pitched propeller would be.

Matt

I will check out the prop but I find it hard to believe. The Honda outboard shop in NJ installed the motor and sold the boat. Why would they put the wrong prop on it?

DaveC426913 wrote:I will check out the prop but I find it hard to believe. The Honda outboard shop in NJ installed the motor and sold the boat. Why would they put the wrong prop on it?

Because it's almost impossible to know what prop is best without putting the boat in the water under your typical conditions. Motoring ballast in or ballast out will change the best prop. If you typically have 1000lbs. of crew and cargo you'd be in a different prop for your conditions.

Outboards ship with a stock prop that does not take into account what boat it's being put on. Almost certainly that's what you've got. The reason that the factory sales sell E-TEC 60s is because they happen to ship with a prop that happens to be just about right for the boat. Most other outboards are shipping with props designed for pure powerboats.

After several days of scouring the forums' I decided that the Solas Amita 4 Blade 11.8 x 9 from iBoats.com was the way to go for my Honda BF50A. I haven't put it on yet, but yesterday with the stock prop, two people, and no balast I got Her up to 16kph (my best yet) Yea Haw, I love this boat

Don't buy the Solas prop. It does perform much better than the 3 blade stock prop that came with my BF50 however they all make a really LOUD annoying "singing" noise between c. 1500 and 2400 rpm. It is likely to drive you crazy. Apparently, you can take it to a prop shop and have the trailing edge filed sharper to cure this but I haven't done it yet. I suggest you search for Solas +singing before buying.

How much can I expect to lay out for a prop, if that's part of the problem?