lets talk trimming the motor

[Rich27028]

on the flats boat i had , the motor had tilt and trim - as i came up on plan i would trim the motor up to level the boat and control porpoising -
now that iv gone to a simpler style of boat - 16ft lowe/w 30 yamaha - i dont have tilt and trim -

my question - on plane how do i control porpoising - and keep the bow under control--???

 

[Johny25]

Got to get more weight in the bow and have the cavitation plate on your lower unit level with the bottom plane line of your boat

 

[cva34]

How easy we get spoiled..Kinda like the TV remote..The above answer pretty well it and of course Trim tabs ...cva34

 

[Johny25]

I have a 30hp on a 14' lowe which makes porpoising even worse and more difficult to deal with. Takes about 150lbs in the bow to keep her from bouncing across the water.....but man she is fast

 

[Rich27028]

the point is - you need the weight added to the bow after you get the boat up on plan-- not before - you want the front to rise and climb upon the top of the water - then as you trim up the motor the bow will be pushed down and the steern will rise to met it -at that point your level and on top of the water -
as chop increases or you experience porpoising you back off the trim until the boat settles down and rides smooth-
my motor is mounted at the right height - full down trim and the cav plate is with in 1/2 in level with bottom of boat -
im used to a center consul flats boat - runs super fast - and runs in real skinny water-
CVA- do you have any idea what a set of Bennet trim tabs cost-?? - good idea but i cant afford it
wrong trim boat squilly and wanders - wrong trim boat wants to switch ends - not good -makes wifie grouchie --

 

[krawler]

https://www.nauticusinc.com/smart_tabs.htm


The St980-30 or -40 will run about $140.00 or less.

 

[Buddychrist]

Pin the motor down until it grabs the water or add weight to the bow

A nice 20+ gallon cooler full of Ice up front strapped down will work nicely and give you plenty of weight

 

[Johny25]

the point is - you need the weight added to the bow after you get the boat up on plan-- not before - you want the front to rise and climb upon the top of the water - then as you trim up the motor the bow will be pushed down and the steern will rise to met it -at that point your level and on top of the water -
as chop increases or you experience porpoising you back off the trim until the boat settles down and rides smooth-
my motor is mounted at the right height - full down trim and the cav plate is with in 1/2 in level with bottom of boat -
im used to a center consul flats boat - runs super fast - and runs in real skinny water-
CVA- do you have any idea what a set of Bennet trim tabs cost-?? - good idea but i cant afford it
wrong trim boat squilly and wanders - wrong trim boat wants to switch ends - not good -makes wifie grouchie --

If your boat is light enough in the bow to porpoise then adding the weight before hand will be no issue to the motor picking up the bow. I can put 300 pounds in my bow and my 30hp still picks it up easily. Oh but that's right I have a Johnson :lol: Try a dry water cooler, I think a yamy can lift that up ha ha ha

 

[Johny25]

Before you buy anything put more weight in the bow and try a new pin slot and see what happens

 

[Rich27028]

guys thanks for all the advice- i havent had it on the watert yet - from past experance with a salt watewr boat maybe im out thinking all this - i do understand trim while under power - and when the tides running and your trying to get in the inlet with a following sea - trim is dam important -- bettet men than me have died ramming a bow under water-- i- we - fish the interacoastal and inlets at ocean isles beach NC and tubbs inlet -- little river jettys and the grass flats-- new boat new experance --

gees i miss my flats boat - mckee craft cape fear 16 with a 115 suzuki--

 

[Buddychrist]

When you are heading in just get a wave 10 feet away from the transom and ride it in

Heading out have the cooler near the middle or rear and then just move it to the front when heading back

 

[cva34]

the point is - you need the weight added to the bow after you get the boat up on plan-- not before - you want the front to rise and climb upon the top of the water - then as you trim up the motor the bow will be pushed down and the steern will rise to met it -at that point your level and on top of the water -
as chop increases or you experience porpoising you back off the trim until the boat settles down and rides smooth-
my motor is mounted at the right height - full down trim and the cav plate is with in 1/2 in level with bottom of boat -
im used to a center consul flats boat - runs super fast - and runs in real skinny water-
CVA- do you have any idea what a set of Bennet trim tabs cost-?? - good idea but i cant afford it
wrong trim boat squilly and wanders - wrong trim boat wants to switch ends - not good -makes wifie grouchie --

Yes I do !Had them on my big boat. I was just mentioning another way to do it..cva34

 

[PSG-1]

My Triton 1650Sc rigged with a 2 stroke Merc 50 had a bad problem with porpoising, especially with 24 gallons of fuel and 2 batteries in the stern. Even a doel-fin cavitation plate didn't stop it from bouncing.

I moved one battery and one fuel tank forward (after doing some modifications to the boat, making a large platform on the front with storage underneath) and this eliminated the porpoising.