how to determine kicker mount angle and starboard strength?

[chiroken]

Hello, been searching the archives without success. I need to have a fixed horizontal mount made to support my 9.9 4 stroke. It will be mounted to my molded horizontal swim grid ('07 Maxum 1800). How do I figure out what angle the actual mounting plate needs to be at to properly mount the kicker? The kicker's function will be periodic salmon trolling and as an emergency motor.

The fellow I plan on using to make the mount made one for a friend to hold his 15hp kicker. It looks like he used aluminum that has that checkered pattern (like they use for truck boxes). Is this starboard? I've read here that some feel starboard is a weak material. Any comments?

Thanks in advance.

 

[JimS123]

Re: how to determine kicker mount angle and starboard strength?

That's called diamond plate. Starboard is the right side of the boat. I don't know about strength, but I would want something flat so that the motor would hold better.

If I were building what you describe I would use two pieces of 1/4" thick aluminum angle, 2x2. Sandwich a piece of 2" thick marine plywood in between it and extend it up high enough so that the motor clamps hold securely. Build a second piece and mount on the bottom of the "swim platform" so that the entire OB transom bracket is supported. Bolt everything together, including the motor to the bracket.

Now, having said that, are you sure your swim platform is strong enough to handle it? And is it thru-bolted?

Angle the bracket parallel with the transom if you can, otherwise vertical may be OK too. Remember, the motor has an angle adjustment as well. You will want to set the cav. plate parallel with the bottom of the boat.

 

[chiroken]

Re: how to determine kicker mount angle and starboard strength?

Yes I know starboard is the right side of the boat- lol! Perhaps I misread the posts and the weakness was referring to the swim grid itself, on the starboard side? Gave me a good laugh though...

I believe the swimgrid is strong enough. It is a continuous mold with entire stern of the boat, there is not a vertical transom of any kind. Just below and behind the grid it is curved, don't see how anything could be mounted to that. The under side (interior of the swimgrid) is accessible from the motor compartment (I/O) and I plan on using a plate rather than just large washers on the underside.

This is a picture of the same boat I have:

http://www.sella.co.nz/images/thumb/7/g/m/5jv7gm-390x292.jpg

Any thoughts?

 

[Silvertip]

Re: how to determine kicker mount angle and starboard strength?

You can't determine that angle unless the boat is in the water. Using an angle finder (Sears, Home Depot, Lowes, etc) determine the angle of the surface you plan to install the mount on. Ideally the vertical part of the mount would then be 90 degrees from the surface of the water. This will provide a trim adjustment on the motor from slightly IN to maximum OUT. If you get the angle wrong, you won't be able to get the kicker 90 degrees to the water (too little IN trim). OUT trim would not typically be an issue since the engine is designed for much more OUT than IN.

 

[JimS123]

Re: how to determine kicker mount angle and starboard strength?

OK got a laugh too. I never heard the term "swim grid". What you have is what I would call a built in swim platform.

Most transoms that mount OB motors are not vertical, but rather angled at about 12 degrees. If you mount the plate perfectly vertical I would be afraid that you might not have enough adjustment inward. If you mount it with too large an angle, you should still be ok.

 

[chiroken]

Re: how to determine kicker mount angle and starboard strength?

When the boat is in the water the swim grid/platform is essentially horizontal. I haven't measured it, but eye-balled it is pretty close. This will change slightly based on how the boat is loaded of course. And I will be adding 96lbs of kicker to the back (no additional fuel tank, I've already decided it will be tied into the main I/O tank), 2 scotty downriggers, and when trolling I will most likely be near the back of the boat (unless I really splurge on an EZ-steer, not to start though).

Considering boat load will vary based on myself or another adult (or my 2 young kids) with me, do you feel I would be safe to have the upright portion of the kicker mount angled 12 degrees then to the swim platform?

 

[JimS123]

Re: how to determine kicker mount angle and starboard strength?

I'd completely load the boat up before making a decision. The true angle of the platform is the key.

Also, that setup is going to be hard to steer. I'd seriously consider the EZsteer. I made one myself for less than 10 bucks.

 

[Silvertip]

Re: how to determine kicker mount angle and starboard strength?

Why mount it at 12 degrees if the swim platform is parallel with the water??? The kicker must sit 90 degrees to the water to permit proper IN-OUT trim as was explained so if the platform is parallel to the water, the mount should be 90 degrees to the platform. The transom angle has nothing to do with this unless you happened to mount everything to the transom (which is unlikely since the platform would be in the way).

 

[chiroken]

Re: how to determine kicker mount angle and starboard strength?

My apologies for the confusion on my part, first time mounting a kicker...

Silvertip...I misunderstood, thinking that the upright part of the bracket should be at a 12 degree angle to the vertical. I assume the typical transom mount kicker bracket would then take out that 12 degree angle so the motor is essentially vertical.

If the goal is to have the motor vertical, and my swim platform is horizontal, then you are correct in that the bracket angle between the horizontal and upright parts are simply to be at 90 degrees.

Sound right?

 

[JimS123]

Re: how to determine kicker mount angle and starboard strength?

No, not right. The mounting bracket on the OB motor itself is not vertical. Transoms are not vertical. The motor's bracket is angled in the opposite direction so that when you put it on the transom the leg will be vertical.

Store bought OB motor retractable brackets have the transom mount and the engine mount parallel. Then when you mount it on the transom, the engine mount will be parallel with the transom.

If you mount your bracket vertical, you may not have enough inward adjustment of the motor.

 

[chiroken]

Re: how to determine kicker mount angle and starboard strength?

To actually see how my kicker hangs I mounted it on a 2x6 across the shop door. With the kicker in the maximal down position it hangs very close to vertical, perhaps only a couple of degrees off. I was surprised by how vertical it went. When in the up tilted position the leg was slightly below horizontal.

I'm unfortunately not in the position right now where I can load the boat and get it in the water.

 

[xeddog]

Re: how to determine kicker mount angle and starboard strength?

I just scanned over the comments so I hope this is not already been said. But it sounds to me like you are asking about the product called StarBoard. That is one of these polymer products and here is one such manufacturer.

StarBoard

It is fairly rigid, but I don't know if it is strong enough to hold up an outboard motor. Maybe someone that has experience using the product can answer.

Wayne