TI outboard mount

I do the opposite, I have my motor mounted on the side opposite the sheet lines. I mount my motor as close to the hull as possible. This allows easy reach of the tiller arm while seated even though it is on the side furthest away from the hull. Same placement of the mount, as far back so as not to hinder the opening of the rear hatch. Note the splash guard because of the proximity of the motor next to the hull.

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Mark
Tandem Island- 2013
2 - Sports - 2014

I also mounted my motors very close the the hull and angled the motors a little so the props are a little under the boat hull. This way when I on a tack with one ama way up in the air the prop doesn't cavitate, and steering is a little easier.

When I had my motor mounted too far out, while motoring with the motor on the right side of the boat I had trouble turning right with the rudder. Moving the motor in and tilting it slightly fixed the issue.
FE

Thank you guys. This helps. I have somewhat different plan for my mount, so when all is well and done, I will post some pics. stringy, Thanks for the detailed spec. I was guessing 6" over the gunwale based on pictures. You have yours almost 9"! This is something to consider. CR Yaker, I love the simplicity of your mount. I am not sure how much twisting forces the motor produces, so my design is more on the rigid side. FE, as usual, You are a wealth of information. I hope to post some pictures soon when I will have something to show for.

So this is my design. Still need to weld the pieces together. Need to drill 4 holes for attachment hardware on each side, and figure out the piece the motor will sit on. I am hanging the TI all the way up to the ceiling of my garage and don't want to lose height by raising the overall kayak height.

Note that I choose the location right behind the scupper holes. I will be able to use them to store the cart while on the water. When the motor is up, it will sit right behind my shoulder and our of the way. Also, I wanted the motor as close to the hull as possible. On the right side, the motor throttle grip is right by my shoulder. I can twist it to the right, but to the left, the handle interfere with my shoulder (based on motor mounted as closed to the hull). On the left side, with the handle on the far side of the motor, I can reach it and steer the boat with the motor if need be. I also like the fact the sail lines are not on the same side. I like to keep the back of the yak low. I think this is going to deal with the up, down and twist forces without any troubles.

There is aluminum back plates inside the hull, thus the close proximity to the rear port hole was handy for installation. That mount is extremely rigid, there is no give to the mount, the kayak will move first.

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Mark
Tandem Island- 2013
2 - Sports - 2014

Hezi,
A couple of comments on your mount design:
-Why so close? Outboards are noisy and the further back it sits the quieter it will be.
-How are you going to get the height necessary for the outboard transom plate? You don't want any part of the outboard clamps and bracket below the gunwale.
-An outboard mounted very close to the hull creates splashing from the prop flooding everything in the rear well, necessitating splash guards like Walt and CR Yaker have fitted.

I'm not sure of the conditions you sail in but any mount that sits on the gunwale and cantilevers out will catch waves. I raised my mount 50mm above the gunwale to avoid this. Prior to raising the mount we had one very wet trip where the motor (and me!!!) got hit by splash from all directions when waves hit the mount. Unfortunately I didn't get any video of that.

You can get an idea of how waves can hit the mount in this slomo clip. View it full screen. Note how the raised mount avoids most waves. Imagine if the mount was at gunwale height. Sailing heeled over makes it worse.

You can also see why Hobie got rid of the handles!

Nice video, Stringy. Thanks.

So this is why I have no handles on my TI? I actually fitted 2 pairs of handles one on each side of each seat...
Stringy, I read this whole thread fishing for information and Google various pictures and videos of motor mounts on islands before setting my mind on my design. I live 10 minutes away from midtown NYC and it's still cold here, it'll be sometime before putting it to the test. Now correct me if I'm wrong, or if I was missing any important point;
The motor on the left closer to the hull means more centered weight and the ability for my long arm to reach the throttle arm and steer the boat in the event of rudder failure. With the motor on the right, it needs to be away from the hull in order for the throttle arm to turn w/o hitting my shoulder. If I will have to fit a splash guard, so be it. Closer to the hull also means prop stay under water in event of ama up in the air. At one point I entertained building a frame that would put the motor behind the rudder. Users here killed the idea by reminding me that in rough conditions, the front and rear are first to go under water, and on sail boats you better keep the weight in the center. With my 100+ kg body seating in the back, the rear is low w/o a motor as is. I am planning to go out in rough seas so this is a big concern for me. The current latitude location means folded, the motor is right behind my shoulder and not in the way. The cart is going to be plugged in the same scupper holes behind my seat which is how I like it. I should be able to recline the seat all the way back w/o conflict. My design is 20cm forward than yours. I can't imagine it will make a meaningful difference in noise level. Either was, I will bring ear plugs along. In terms of transom plate, I am still working on a removable one. My TI is hanging from my garage ceiling on a platform attached to an ATV winch trough a series of pulleys and cables. When up, my whole 6'3" (193cm) fit under with room to spare. I don't want to give that up. As for height, from pictures I figured most transom plates top edges are at 6" from gunwale. Yours is almost 9". I realized maybe the 6" sailing in calmer water? I am working on an aluminum / wood combination where I can adjust height at very little cost. Last I want to address the transom plate base in relation to gunwale; for me to lift it at this point means to weld another piece of square tubing on top of the existing one, or to redesign the whole thing. From a) the pictures I reviewed, you are the only person raising the base over gunwale. I am sure it's the smarter thing to do, but at this point I am keeping it the way it is and hoping forward location = less waves and/or maybe I will go around it with a small deflector.

Let me know if you think I am wrong. This is work in progress and I can always start over.
Thanks!

Stringy, I take it back, I watched your video again. My mount will put the motor a lot closer to my head. It'll be louder, but I think the bottom of the transom will catch less waves at gunwale height.

Hezi,
Mounting an outboard on the TI is very much a learning experience, so be prepared to tweak your mount as needed.
Are you going to weld the square tube sections on top of each other to form your transom mount?
If so it would be easy to add a lower section that was only as wide as the gunwale. This would lift your mount enough to avoid most waves.
What size tube are you using?
The other advantage with a high mount is that you have less drag on the outboard. The Suzuki manual states " a motor mounted too low will increase drag, causing reduced speed." Too high of course has to be avoided as well. That 22.5cm distance above the gunwale for the top of the transom plate works well where I have the bracket mounted.

I posted the video to demonstrate just how high waves can roll over the gunwale of the TI. We get those conditions a lot around here and after just one unpleasant trip I was convinced to raise the mount 50mm above the gunwale, which solved most of the wave action problems.
From what I have learned in this thread and my own experience I can say that these are important points to consider:
- the further back the better.
- the higher above the gunwale the better.
The position just forward of the rear hatch seems best. It was CR Yaker who first mentioned that and it made sense to me. The outboard is easily reached for starting, refuelling, raising etc and can be fully turned if needed. Those with their mounts in the middle of the rear deck chose that location for the ability to use the rod holders as part of a removable mount, it seems? I preferred to have the access advantage that the rear hatch gives for through mounting. As sound/ distance is exponential it is also quieter, though you are right in that a 20cm or so difference would be noticeable.

As far as being close to the hull, I have been tempted to move mine in a bit but haven't done so because with the motor raised, when sailing only, on certain reaches the mainsheet gets very close to the outboard.

I hear you guys about the motor noise problem (pun).
My thinking is different from most. The normal thinking on outboards is they only provide the rated horsepower at near max rpm, so everyone runs their engines at high rpm, (really loud).
In order to be able to run my motors at a much lower and way quieter rpm (and way more fuel efficient), I re-prop all my motors with higher pitch propellers. This way I can run them all day at just above idle, and they are very quiet (especially with underwater exhaust). It takes around 3/4hp to propel my TI to 6 mph, with my twin outboards 1.5 hp (2 x .75hp) propels my TI to 8 mph all day long, then when I add the sails, wings, and pedal (tri-power) the boat goes faster of course. A little faster in very low winds, and much faster in higher winds. The throttle always remains the same.
Basically If I want to run at 6 mph I run one motor, (with the other one tilted up) if I want to run at 8mph I run both. (I seldom run at 6 (lol))

When running the motors are very quiet and we can easily talk over them, in most of my videos, you can't even hear the motors running and I talk thru the videos.
I get 2.5 to 3 hrs runtime per tank (each tank holds 1 liter), and almost never run out of gas out on the water. (3 hrs @ 10 mph is 30 miles), I have to have at least a little natural wind to hit that economy thought (5-7 mph). I can afford a dollar in fuel for the day.

I very seldom go over 10 mph because the boat is quite a handful and exhausting to operate at higher speeds, just not worth it to me.

Just tryin to describe a different approach, that might be of interest to some.

FE

Very good Bob!
I never operate the Suzuki flat out though. No need to as at 1/4 to 1/3 throttle the little Zook will push the TI between 10-12km/h, depending on conditions for about 1hr 15 mins on a litre of fuel, motoring only.
Flat out it might push the TI to 14-16km/h but I just don't see the point in operating it like that.
To me, the noise is the biggest disadvantage with adding an outboard.

Last November I had a months annual leave and gave the TI and Suzuki DF2.5 a good workout. We did lots of day trips on enclosed and open waters in varying conditions from zero wind to 25 knots+.
Also did a 10 camping trip to Myall Lakes, where we were joined by our daughter and her family for a few days. We moved a lot of gear that trip and the outboard really proved it's worth. It helped a lot in strong winds, yet raised up allowed normal sailing and you forget it's there.
We reckon it's the best upgrade since the haka!
A few clips:

Reading this thread has left me marveling at the skill and ingenuity of the posters here. I would love to have an outboard mounted on my TI. Too often the winds quit and I'm reduced to pedaling, something I don't enjoy. Unfortunately, I don't have the skills or the equipment necessary to take on a project like this. Is there anyone on this board who has a well-working mount who would consider selling me some kind of kit version?

Brunswickian:
For those who can't build their own motor mounts there are several outfits that sell motor mounts for Hobie kayaks and AI/TI Adventure boats ready made, here is one:

http://www.islandhopperoutboards.com/ka ... hobie.html

I made mine out of just simple PVC tubing, it didn't take an hour to make and only cost about $20 bucks total (my only tools were a hack saw and electric drill), I picked up all the PVC, wood, and aluminum at Lowes. I have twin big ole Honda outboards hanging off my mount. Actually I still have the single engine mount I made 6 yrs ago, hangin in the garage, has thousands of miles on it, but it still functions just fine (just looks really crappy because it's old, and was used in mostly salt water). My twin mount's been runnin 3 yrs now and also has thousands of miles on it (same exact design). It was all laid out in detail on the Ultimate Tandem Island thread.
viewtopic.php?f=69&t=33720&hilit=ultimate

If you get the Island Hopper mount and hang a Honda or Suzuki 2.5 hp motor on it, I would tie a spectra string (hobie rudder line) to the lower unit, to counteract the thrust of the prop, and tie it off somewhere near the stern (you could just tie to the gudgeon at the back of the boat if needed).

The outboards just cost money (you could build your own engine from scratch, but why) The outboards these days are very reliable and fuel efficient (just not cheap (lol)), just buy it hang it on the boat and pull the rope to start it, really nothin else to do.

I'm not sure you need to go overboard, we use our boat for far offshore in the gulf (mostly for scuba diving) (my setup is way overkill, and absolutely not neccessary for 99% of the owners out there). Unless you really know your stuff I highly recommend nobody do what I did.
FE