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Discussion Starter · #1 ·
This following information was taken from this page under the fair-use doctrine.

I'm posting this and the next article because of Kook's problem with Chine Walking after installing a new 680 HP engine in his 24' Agressor listed in the Sunsation Section of the forum

http://www.land-and-sea.com/marine/faq-marine.htm

MY BOAT NOW HAS MORE HORSEPOWER THAN I CAN USE. WHAT CAN I DO TO IMPROVE ITS HANDLING?

Well on outboards, after installing dual steering and properly adjusting out steering cable backlash, the next step is to add rigid motor mounts to reduce the fish tailing that causes dangerous chine walking. Chine walk is the tendency for your boat to oscillate back and forth between its port and starboard chines.

Installing a dash controlled jack to raise the prop at high speed will help top end and greatly reduce chine walking because it preloads the steering system with prop torque.

A nose cone and torque tab can help reduce the steering torque the driver feels at high speeds that are due to the "paddle wheel" effect of surfacing, high rake props, and the angle at which the engine has to run through the water. These modifications also can prevent chine walking.

For stem drive applications the most effective modifications you can make are the Stern-Jack, nose cone, and dual steering. The Stem-Jack improves handling for the same reason a hydraulic jack plates helps an outboard motor -- it preloads out the steering cables' backlash so that at high speeds the drive won't "fishtail" and causes chine walking.

Other items of importance to driving control are a foot throttle and steering wheel trim buttons. They allow you to keep both hands on the steering wheel all the time, and react faster to changing conditions. You will always be able to drive faster and safer under any conditions with these two easy modifications!
 

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Discussion Starter · #2 ·
here's more:

Chinewalking, what is it? - by Jeff Bristow
Can it be cured? Chinewalk happens when the boat has the ability to run with little wetted surface. The boat is trying to run on a small pad, once it falls off this pad, it falls to one side then bounces over to the other side. Hence chinewalking!

check this out: http://www.scaryfast.com/Homepage.htm

- jeff
 

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Now this is a subject I know something about. In 1992 I bought a brand new, made for me, 22 Progression outboard. My first custom boat and I was extremely proud when I brought it home. Imagine my dismay when, on the first trip to the river, I could not go over 60 without the boat chine walking like a drunken sailor. I had seen Kevin (Loughran, the owner of Progression) drive the boat at 70 effortlessly so I knew the problem was with ME:eek: . Well, over the course of that summer I learned to drive the boat and keep it balanced on the pad eventually achieving speeds over 70 MPH with rock solid stability. I believe that most boats can be balanced like this once you develop the knack for the steering input required. This presupposes that your boat is equipped with tight steering and some of the goodies mentioned above. My boat already had solid mounts, Latham steering, foot pedal trim and foot throttle so the rest was up to me. When you first try this you will swear that it is impossible and I don't know your boat and no one could drive through the chine walk on (fill in your boat and motor combo here). I felt the same way but I KNEW that Kevin could do it so I couldn't say it was impossible. By all means make the mechanical upgrades first but if it still walks then try to learn to drive through it. If you succeed, you will feel a sense of accomplishment and self satisfaction.:cool: Questions anyone?
 

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Discussion Starter · #4 ·
laster, why don;t you come down to the chesapeake bay and maybe you can help me get my stinger past it's chine walking.

It gets real scary around 80 mph (4,500 rpm) and I have to back-off.

bring a life-vest and a drag-chute just in case....

:)
 

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Cmon Jeff,,, go for it,,, whats the worst that can happen !!!!
 

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Well I see it as NO GUTS NO GLORY there Jeff!!!:bandit: :bandit:
 

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OK Jeff,,,,, The challange has been laid down !!!!
 

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I would love to Jeff but it is not the kind of thing I would expect to accompllish in a single 15 minute session or even in a hour. It takes a certain amount of wheel time before anyone is comfortable with the handling of a particular boat - me longer than average. Now if I could borrow the boat for a couple of weeks . . .:D :D
Seriously, I wish I had the time to run down to visit you. I would love to check out your other boat too. Maybe in my next life.:(
 

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Hey Jeff, remember when you race motorcycles and you push the bike to the edge of control, without going over it. Then to go faster, you stretch out the edge even more, but still in control.
You learned to do this by making many, many laps, correct ?
This goes the same for chine walking. Pushing the boat to the edge of control without falling off the edge.
The only way to learn this is by many hours on the water at speed. When you made faster laps on the bike, you made very small adjustments each lap. This is what you do for chine walking.
Most of it is in the steering, by making very small corrections to the left and not overcorrecting which just takes time to learn. You also need to learn to read the water as you would read the track on the bike. Another trick to help with chine walking is to use your hydralic trim tabs with the switch's mounted on the steering wheel. When making the left corrections, lower the left tab also. Just takes lots of practice. You can actually learn to make a boat dance when you get enough hours run.
Most important is to know the boat. As you know, no 2 boats act the same just as no 2 bikes drive the same on the track.

Now the part you won't like. When you're younger, you go for the edge and beyond all the time. (hopefully you get back) When you're older you tend to think more than too react, but your also more wise at what you can do or can't do. So if your thinking twice on pushing it, STOP ! That second think will get you into trouble every time. 60-70 mph is fast enough for most people. So sit back, drive the boat where its comfortable and enjoy.

Sorry to spout off, just an opinon, but I been there, done that and that why I'm in the shape that I'm in. But man, was it ever Fun !!! :D
 

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Discussion Starter · #12 ·
waddaya mean?

I kept falling off!

I'll take some pictures of my old race leathers hanging in the garage soon and post them. People just shake their heads asking me how I ever survived...

speaking of surviving... how about this one?
1997 Daytona 200.
Jeff does somersaults at 100 MPH!

:)
 

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JEFFJ said:
People just shake their heads asking me how I ever survived...

speaking of surviving... how about this one?


:)
Like I said, been there, done that, only on the dirt flat track at the Indiana fairgrounds. Result; broken back, left leg, both ankles, now I'm held together with steel, pins, etc. !
And I bet you're ready to do it again ! :D
 

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The only minor problem with that is the second lap on a bike is just like the first,, you know when the bumps, hills, slick spots etc are,,, no two laps in a boat are the same !!! Mother nature,,,, what a [email protected] !!!!
 

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Well I wouldn't say every lap is the same, it will change from lap to lap. Jeff will agree with me here, people will blow motors and oil down the track and folks will throw dirt up on the track. So what was a nice 120mph corner is now slick as owl Sh*t . :laugher: :laugher:
 

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1boatnut said:
stuchamp-you must have one hell of a time thru the airport metal dectors:D
I carry a card, but the only time I had a problem was at the Dallas airport. Had a real nice gal do the once-over though. :D
Also got patted down by the Secret Service at the Book Depository Building (JFK museum) in Dallas. :gunner: :eek:
 

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Discussion Starter · #20 ·
THAT'S HOW i GOT INTO THAT MESS IN THE PICTURE ON THE PRIOR PAGE...

Track was fine but my front tire was going away after 32 laps at Daytona and a faster guy passed me going into the horshoe and my testosterone over-ruled my head..... just twisted that throttle a little tooooooo far :)
 
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