Personally, when I fitted one to my F 30 Yamaha
it slowed my boat down 5-6 knots on the top end . But planning was out of the water in half the time . Drilling holes in a newish outboard was hard to do .

Years ago we fitted wings to the engine on the family boat. The engine was a Suzuki 9HP and had trouble getting boat, which was a tinnie on the plane. The wings helped get the boat on the plane. We did not care about top speed.

The engine came to a premature end as it was not securely connected to the boat and on the way home it fell off the boat and was destroyed when it crashed on the road. Fortunately no one was driving behind the towed boat. My parents bought a more powerful motor after this. I think it was a 15HP Johnson engine and it had the power to get the boat onto the plane.

Flatty said..
Yeah i have one on a yamaha 30hp 3 cylinder 2 stroke. I originally bought it because my boat (haines hunter seawasp) would "bounce" at full throttle and fall of the plane.

It fixed the two issues that i wanted fixed but came with a couple negatives. First it makes the boat about a knot or two slower. I used to get about 25 knots flat biccys, now i get 23.5/24 knots.

If i am going diagonal to waves the tiller becomes "heavy" and tries to pull out of your hand. My mate has a 50hp tohy on his wasp and it is worse. You nearly need to be Arny to hang on to his at WOT on a choppy day.

Overall i am happy with it. I dont really care about the top end loss, but the tiller is a pain in the arse if you know that you have an hour plus trip to the ramp and the weather is going to turn sour.

you need to raise the motor. that will fix this.

Flatty said..
Yeah i have one on a yamaha 30hp 3 cylinder 2 stroke. I originally bought it because my boat (haines hunter seawasp) would "bounce" at full throttle and fall of the plane.

It fixed the two issues that i wanted fixed but came with a couple negatives. First it makes the boat about a knot or two slower. I used to get about 25 knots flat biccys, now i get 23.5/24 knots.

If i am going diagonal to waves the tiller becomes "heavy" and tries to pull out of your hand. My mate has a 50hp tohy on his wasp and it is worse. You nearly need to be Arny to hang on to his at WOT on a choppy day.

Overall i am happy with it. I dont really care about the top end loss, but the tiller is a pain in the arse if you know that you have an hour plus trip to the ramp and the weather is going to turn sour.

you need to raise the motor. that will fix this.

tiller heavy. it will also improve economy and just about everything else. you wont loose the benefits of the foil. also try moving the trim pin out one or two. you don't want any negative trim

myusernam said..
tiller heavy. it will also improve economy and just about everything else. you wont loose the benefits of the foil. also try moving the trim pin out one or two. you don't want any negative trim

Yeah i will give that i try, i dont think it will be the problem though. It was never heavy before the foil. If you want i will post the results back here.

For the prop comment, i have tried three different props. The stock yamaha one, a solas prop with one inch more pitch and a yamaha prop with one inch less pitch. The stock yamaha one works the best for my setup. The solas would give me another 1-1.5 knots with just me and no gear in the boat, but when started loading it up with a couple guys and gear. It slowed down quite a bit and would not pull the revs. The yammy prop with one inch less pitch worked great and kept the revs up when i had a load. With a lightly loaded boat, the outboard would rev its balls out.

Stock yammy prop is a good compromise but if i am taking the boat up as a tender to the reef, i will swap it over to the propellor with less pitch.