One of the best things from a skiing aspect of the 18's has got to be the wake. No matter if you are a slalom skier, barefooter, trick skier, or I dare say swiveler the 18 has one of the best wakes around. Look at the photo below, and I think we all will agree. There is no large lip on the curl like most ski boats today.
Agreed! The baby dyne wake is the best all around wake I have ever seen. It's almost non-existant at barefoot speeds, just enough definition so you know where it is when you need it. Smooth and low for slalom speeds. And with enough trim, you can even get a decent size, good shaped wake for trick skiing (or wakeboarding if you're a sideways type of person). I can't comment on how it is for snivel skiing, since I don't believe I have done that behind an 18 yet.
As long as this topic was brought up again, does motor height have any affect on the turbulence from the prop or even possibly with the wake? How about pulling power? I know for speed boats they try to keep them up high to minimize the amount of lower unit in the water, and the keep 1 blade out of the water at high speeds. Would it make sense to lower the motor a bit for a ski boat to help keep the table calmer, and get plenty of fresh water to push on for the bigger pulls?
My motor is raised a little. It is one mounting hole above the standard height transom. When we went from the 150 to the 75 on swvski1's 17.6 it reduced the turbulence in the wake I believe. There is an interaction between the up swinging prop blade turbulence and the turbulence from the port spray rail. If you lay on the aft deck and look down and aft you can see it. I owned a hot boat that the prop shaft center line was 7/8 above the bottom of the boat. Only the lower blade was in the water. It had no low end pulling power. That is done to reduce the drag at very high speed (above 80). jim
It is my opinion that the motor should be as high as practical and the tow point be as low and as far forward as possible (but not forward of the centerline of the fin) for best tracking and to help reduce the bow rise with big loads. If the motor is too high there will be cavitation problems, specially in the turns. jim
I found this video on YouTube: http://www.youtube.com/watch?v=XacKdQs6PDo A good example of how nice the 18' wake is. I'm guessing it's a 200hp Merc BlackMax on the back.
I think it is the perception of the market that you must have an open bow for the kids etc. I just do not like people in front of me and in fact I do not allow people to ride in front if we are skiing. It is the same with the direct drive inboards. A 19' Ski Nautique is way faster, more fun to drive than a 20 or 21' Open bow that weighs considerably more. But the market has spoken that Open Bows are the place to be. Correct Craft, MC and Malibu produce under 100 closed bow boats per year now. Almost all of the promo boats are Open Bows because that is all the dealers want to sell. Several years ago before the Coast Guard got so involved with small boat builders, Pete had Tom/Skip build a couple 18's one of which is dynebob's now. They just did not sell. I think most people, just like with collector cars, would rather putz and rebuild an old "classic" because they can spend money at their own pace. The problem on our lake is often you have to "get to the other side" for calm water, and our lake is 11 miles long. A 20 with a windshield is better suited for that.
Top Ten Reasons for lack of demand on any outboard ski boat. 1. Advertising - Inboard manufacturers push the inboards in ads and with promo boats, tournament boats, etc... 2. Noise levels (getting much better now with the E-Tecs, four strokes, etc...) 3. Inboards drive like a car right out of the box, so anybody can be a pretty good driver 4. It's easier to make an inboard weigh 4,000 lbs and throw a 4' high wake. 5. Tracking while pulling high end slalom skiers tends to be better with an inboard (makes it easier on the driver). 6. Safety - The prop is hiding under the boat on inboards 7. Convenience - Inboards have a full platform on the back to make putting skis/wakeboards on easier. 8. Fuel efficiency - Also on the way out with the new outboards. 9. Horse power ratings - Non existant on inboards. 10. Hot water hose for warming feet is easier to run off an inboard. Any body have any other reasons?
