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Discussion Starter #1
whats the correct way to trim your outdrive, does it hurt it if you trim alot?? I set my for top mph when I trim past it the mph went down so I brought the outdrive down a hair till it picked up speed again(the prop never did blow out) Im almost at full trim I dont want to break anything
 

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I trim mine for top speed. If I trim it too high, I start to chine walk real bad. I can steer out of it, just gets tiring after a while. Mine is about 1/2 way on my trim gauge. If I look back and see excees spray coming from behind the prop, usaully too high and I loose 1-2 mph when I do that. I have my "sweet spots" where I know where to put it in diffenrent conditions. I can feel the boat start to lossen up when I get it right.
 

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Discussion Starter #3
same here but my chine walk is gone from last year I think the lab 23" prop fixed that
 

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experiment, experiment, experiment....

That's been my experience. Every boat is different. The basic rule of thumb is trim the outdrive out until 1) the boat begins to porpoise or 2) you feel the prop start to blow out.

Trim will vary with conditions. In a 40 minute run yesterday over various condition on the bay I probaly adjusted the trim a hundred times. My finger is always on the trim switch.

Because the Chesapeake Bay has so many tributaries that are many conditions we encounter with winds and currents and YACHTS!!! making waves....

:) good luck and experiement, experiment, experiment....
 

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Just be careful that your sensor on the drive is working properly and set correctly and the lower unit stays within the gimble range. There are slides on the upper end of the out drive that give side support to the lower unit, once you raise it above those, then there is nothing to keep it from twisting.
 

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#1 and #2 BY Jeff are limits on too much trim. Once you ease back down to eliminate them- the best is to fine tune with your tach and a gps. On many boats-you can trim too high without blow out or porpoise-the engine is reving too much but it sounds fast. Watch your gps speed-their seems to be a fine point where max speed and rpm meet-ex, more trim gives a tad more rpm but speed does not change or less trim pulls the engine down in rpm by putting more boat back in the water.

Like Jeff said- this is a constant process at times, based on load, wind and water conditions. But-all part of the Joy of Boating.
 

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Discussion Starter #10
gilla,
thats what Ive been doing (trimming to max mph not rpm) just wanted to make sure I wasnt pushing the outdrivr too much
 

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crmax...like gilla said,its best to use a gps or tach to trim out your boat. There are different reasons for using trim. Top speed,and ride quality.For top speed ,trim out till you engine reaches maxium rpm's......
Ride quality depends on water conditions.


I am not sure if you can get your hands on a copy of either this months or last months Family and Performance Boating,but there is a complete article on proper trim and tab use..... Every boat is different,and like Jeff said,it's all a matter of finding the sweet spot..
Hope this helps
 

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There is a very good article in this months Family and Performance Boating magazine on trimming.
 

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thats the problem with Bnut and my boat,,, we keep gaining MPH even though we are WAY over trimmed,,, mine got better after blueprinting the hull,,, but tap trailer twice and the boat really frees up and gains that last 200 rpm and 4 mph,,, ( also gets a little "dancy",, needs to be flat water )
 

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Discussion Starter #14
I dont have the balls to hit the trailer button, but the rpms wont be a problem I got a couple small nicks in the prop this weekend Im going back to the 21" (going to get the 23" fixed), Im curious on how much trim the 21" prop will want
 
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