Standby OB and Trim Tabs !!

Hello,

I am building a 20ft fibeglass with 125 Nercury OB, I asked the boat builders to include a 10HP OB as a stanby engine and a ladder.
The standby will be installed on the right side of the main OB and the ladder will be installed on the left side.
I also asked for Trim Tabs, however they said the TT's can not be installed becasue of the standby OB and the ladder.
Does this make sense? for those of you who have TT's, pls help.

 

A 20' powerboat of typical transom dimensions would make placement of all that gear (boarding ladder, two engines and tabs) difficult. There just isn't the space, frankly. Each engine will need room to swing for steering and for raising, tabs need be affixed just where typical boarding ladders would live so the conflict is born. Boarding ladders don't have to be on the transom and you may have just enough room to mount the kicker engine inboard of the tab, less the ladder.

I've often questioned the need for tabs on stern drive and outboard applications. Adjusting trim is reasonably easy in these configurations and unless you are overcoming a short fall in the design, shouldn't be necessary. Which raises the question, why build a design that requires the band-aid fix, tabs usually provide. Trim in small craft is usually easily fixed by shifting weight(s) about until you've got what you need. This means a Saturday afternoon moving coolers, portable tanks, ground tackle, etc. around the boat, until you settle on locations that trim her out. If the design is in need of addition trim adjustment, then the builder or designer may have better, less troublesome options available then tabs.

 

Thanks PAR,
Your answer about the Trim Tabs is quite conclusive. I guess I got carried away by TT's although the boat is still under construction. Based on what you said I will wait and see how balanced the boat is and assess the need for TT's then.
Thanks again

 

Most people use trim tabs to adjust the height of the bow and stern during operation. But thats the job of trim and tilt on your OB. Most OB's over 70hp have trim and tilt as standard. Only used TT to alter the angle of your boat if its listing to one side during operation. Image Trim tabs as water breaks. Putting the fin down, increases drag and lowers your speed and economy.

Few people use the OB trim and tilt to its full potential. It aint just to lift the engine out of the water when in shallow water. Its to reangle your boat during motion, increasing performance with the changin seas.