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 Post subject: TI outboard mount
PostPosted: Sat Jan 24, 2015 2:10 pm 
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Joined: Thu Jun 01, 2006 1:16 pm
Posts: 209
Location: Colorado
I just got this 2015 TI and dont tell Hobie I did this.. (warrenty...) but one of the ways I want to use the TI is for day outings with my wife on a big lake (Havasu - nearly 40 miles long) and motor to some area with the 2.5 hp Suzuki (little four stroke- water cooled).. kill the motor and then sail/ pedal.. I had tried this same outboard on my AI, got about 40 miles to the gallon.

I went to an AL surplus store yesterday.. picked up some scrap for about $2.66 per pound. There are some brackets with backing plates permanently mounted on the boat - weigh about 0.25 pounds. The outboard bracket weighs 3 pounds. Seems to be very sold.

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 Post subject: Re: TI outboard mount
PostPosted: Sat Jan 24, 2015 5:48 pm 
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Joined: Thu Jul 07, 2011 12:57 pm
Posts: 211
Location: Delaware Coast
Very nice - I like aluminum :)

I prefer the mount to be farther back towards the stern so that I can move the tiller behind my back when needed, but that's just my preference. However, I think I see something that you aren't going to like. I think that when you are sailing and leaning towards the starboard that the mount will dip into the water and cause noise and splash when you hit waves. Set up as pictured below, the splash hit me just about in the back of my armpit. Didn't bother me wearing a drysuit, but when spring came around I started hating it.

Since that picture was taken, I extended the pipes in the rod holders by 1.75 inches raising the bottom of the mount to 2.25 inches above the gunwale and the problem is solved.

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 Post subject: Re: TI outboard mount
PostPosted: Sat Jan 24, 2015 6:00 pm 
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Joined: Thu Jun 01, 2006 1:16 pm
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Location: Colorado
Quote:
starboard that the mount will dip into the water and cause noise and splash when you hit waves


Hmm.. that wouldnt be good.. when I tried this with the AI it was a calm day - no waves.


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 Post subject: Re: TI outboard mount
PostPosted: Sun Jan 25, 2015 11:59 am 
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Joined: Thu Jun 01, 2006 1:16 pm
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Location: Colorado
I took a look at my setup with the outboard in the up position and for my case, it would be the bottom of the outboard mounting bracket that mainly would be catching waves. So what I did to improve the wave splashing problem is to leave the main bracket in place (keep it as robust as possible) but raise the part of the bracket that outboard rests on by 1 5/8 inch. This should at least reduce the splashing problem. This is a short shaft water cooled outboard and the prop is still plenty deep.

I also made a few other changes.. not done yet but I think this is close to being ready to try out.

FYI, one of the goals of something like this is to be able to easilly REMOVE it. I probably wont use the outboard very often..

The first picture is before - you can see the bottom of the outboard mounting bracket sticking down a ways.. I can see this catching waves.
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All the rest of the pictures are after raising the outboard 1 5/8 inch
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FYI, this is what the fishing rod holders look like inside the hull (they are not bonded to the hull at the bottom)

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 Post subject: Re: TI outboard mount
PostPosted: Sun Jan 25, 2015 12:26 pm 
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Posts: 209
Location: Colorado
I was watching the DVD that came with the TI and it shows some electric motor/battery options which I thought was interesting. In the picture below you can see another little planning hull sailboat that I also use a fair amount during the summer and I can put either a 30 pound thrust electric trolling motor on it or the 2.5 hp gas outboard (there is a group 25 lead acid battery just below the mast location on the monohull). It turns out that almost all the time, I use the electric trolling motor - two reasons for that. One is that it only weighs 13 pounds on the transom, second is that I onlly use the trolling motor to get away from the dock (usually somewhat busy).

With the TI, the electric trolling motor need is completely taken care of by the mirage drive or by padeling. Its only the real long distance motoring that I will the little 30 pound gas outboard but it works the best for this.. you will go crazy fron listening to the outboard noise trying to burn just 1/2 gallon of gas..

I just wanted the option..


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 Post subject: Re: TI outboard mount
PostPosted: Sun Jan 25, 2015 1:53 pm 
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Joined: Sun Apr 20, 2008 6:18 am
Posts: 1626
Location: Sarasota,Key West FL
Actually I have my paddle mounted to the side of the boat. The paddle helps prevent splashing the motor.
Bob


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 Post subject: Re: TI outboard mount
PostPosted: Sun Jan 25, 2015 5:38 pm 
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Joined: Sat Dec 06, 2014 3:13 am
Posts: 4
Location: Brisbane
Quote:
FYI, this is what the fishing rod holders look like inside the hull (they are not bonded to the hull at the bottom)

Is this different from previous versions of the ti ?


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 Post subject: Re: TI outboard mount
PostPosted: Mon Jan 26, 2015 10:15 am 
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Joined: Sun Apr 20, 2008 6:18 am
Posts: 1626
Location: Sarasota,Key West FL
Ictus:
The rod holders are the same as my 2012 TI, they are not attached at the bottom of the hull and can't really take much load at all. With motor mounts all the forces need to be taken up by other means, the rod holder pockets are just a location holders for the motor mount (it's always been that way).

I have twin Honda's on my TI and haven't had any issues with the rod holders in the almost 5 yrs I've been running my TI's with motors (I've never gone out offshore without a safety motor installed on the boat)

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Here is a pic kind of showing how deep the props need to be to work ok. (because the boat tilts during tacking, it helps to have the motors as close to the hull as possible, and also tilt the motors slightly so the props are kind of under the hull (or you end up cavitating). I have custom extreme high pitch props mounted on my motors, I get right around 100 mpg with my setup (when I'm using the motors). Obviously if I have enough wind I just flip the motors up (which is seldom around SW Florida and the Keys in the summer).
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The big brown thing on the back of the hull is just a simple planing hull mod I added to my hull so I can get the hull to plane at higher speeds, it also adds 100 lbs of additional flotation to the hull (it's foam/fiberglass and weighs about 7 lbs, and removable if I'm not planning to go fast).

Just a word of caution about using outboards on sailboats(especially with standard pitch props), my TI has massive sails (and wing sails), and I've exploded a couple outboards now over revving the engines (can get very expensive).

Motors and massive sails are not everyones cup of tea, I only have that stuff because I go offshore a lot in the keys (we are scuba divers), and the boat is hardened for offshore use.

I typically only go out in very light winds (under 5-6 mph) and flat seas (the most typical weather in my areas), I'm out there pretty much every weekend.
Like I said, what I have is not everyones cup of tea, here is a short video of me out on a typical Saturday (very boring video). With the motors on low RPM (I almost never use them anything above 1/4 throttle), with the underwater exhaust, they are very quiet, and we have no problems talking over the quiet motor noise (the sound in the video is actual). I consider my boat to be a Hybrid pedal/sail boat utilizing Hobies Tri-power capabilities to their fullest extent.
https://www.youtube.com/watch?v=AaaBSQtlcA8


Bob


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 Post subject: Re: TI outboard mount
PostPosted: Mon Jan 26, 2015 12:45 pm 
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Joined: Thu Jun 01, 2006 1:16 pm
Posts: 209
Location: Colorado
Bob, are those Honda short or long shaft? I know a lot of sailboat people get those because they can get a long shaft. The Suzuki 2.5 only comes in short shaft.. which I think will be OK. The water pump inlet is near the prop (Suzuki problem only - the Honda is air cooled) and you dont want to starve that area for water.. the water pump impeller burns up very quickly.

100 mpg - nice!


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 Post subject: Re: TI outboard mount
PostPosted: Mon Jan 26, 2015 1:47 pm 
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Joined: Sun Apr 20, 2008 6:18 am
Posts: 1626
Location: Sarasota,Key West FL
walt:
I have the short shaft model, It's air cooled but has underwater exhaust, and very quiet ( I like that feature), I only rinse the outside of the motor off when I come home (no flushing needed), and can run the motor out of the water but it's pretty loud out of water.
I used to just keep the motor on the boat for emergency power (hardly ever used the motor), then I made the wing sail, which works on apparent wind so you have to have 5-6 mph of wind blowing over the wing in order for the wing to do anything. If I have two peddlers peddeling we can get enough apparent wind to make everything work, but we get tired to fast (within a mile or two). So I use the motors running at low RPM for supplimental power (with the special high pitch props) to create our neccessary forward motion (works just like an airplane wing with propellers does). With this setup my sails create there own wind so I don't need any natural wind at all, and the actual direction of the real wind doesn't really matter much. In fact my best point of sail is almost directly into the wind since this creates the most air passing over the wing. I made the setup because I use the boat as my exercise program peddling 15 miles every week, used to take 6-8 hrs, now I can get my 15 miles done in about an hr or two, it typically costs me between $.50 cents and a buck per week in gas to go out. Of course If I don't pedal or I don't use the sails and just use the outboards only I get maybe 20mpg but I never use them that way.
I only like to go out in very low winds when the water is very flat because I crushed my spine years ago and just can't take the motion from the boat rocking and the waves with my bad back. In the summer time here when it's sunny with no wind, the TI only goes 2-3 mph pedaling (takes a long time to go my 15 miles), and with no breeze from my forward motion it's like sitting in a frying pan out on the water 10 months out of the year (not fun). With this setup even on very hot days with no wind at all I get a great breeze that keeps me cool, and I can actually get places, some days I do 50-60 milers.

Like I keep on saying, this is not everyone's cup of tea, but it works quite well for me. We love our TI and use it for pretty much everything as our family boat. Obviously I'm not a hard core 'man vs sea' sailer type, I just do what it takes to get where I want to go in a reasonable amount of time (as long as it's less than a buck in fuel for the day (LOL)).
Here is another video showing the outboards with the boat planing
https://www.youtube.com/watch?v=tR9oJL6psds


Bob


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 Post subject: Re: TI outboard mount
PostPosted: Thu Feb 26, 2015 7:44 am 
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Joined: Thu Jun 01, 2006 1:16 pm
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Location: Colorado
Bob, thanks for posting all that, I sort of blame you for me wanting to put a small motor on this (which is a good thing..)

I had some last photo's of what I did and they are posted below. This may be overkill.. but I like how rigid it is. The outboard bracket ended up weighing about 6 pounds, takes under 30 seconds to remove and about 1 minute to install (there is a bracket that alwasy stays on the boat shown in an earlier picture). My peak speed with the 2.5 hp Suzuki four stroke was about 7 knots and it ran about 6 knots at 1/2 throttle. This is at about 4500 ft elevation so I lose a little over what it would do at lower elevation. I took some video running the outboard. I also wanted to try solo from both the front and back seats.

https://www.youtube.com/watch?v=kmkKWrM ... tion=share

One other thing I lke about this more robust mounting is that the outboard is mounted just as rigid either in the down position for motoring or in the up position for sailing. More than likely I will be out in this boat in some fairly high winds going fast with the motor up and it will be good to know the 30 pounds of mass (ie, the outboard) wont move around in windy chop.

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 Post subject: Re: TI outboard mount
PostPosted: Sat Mar 14, 2015 9:00 am 
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Joined: Thu Jun 01, 2006 1:16 pm
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Location: Colorado
I also took a "data point" on the range of that little 2.5 hp outboard (four stroke). The gas tank is .26 gallons and I filled it and ran the TI solo (I was in the back seat) until the gas ran out.

I ran the outboard at 1/2 throttle and the speed was around 5.7 knots (which is not at all bad for an 18 foot boat and that 30 pound outboard). The single tank lasted 1 hour and 22 minutes which works out to about 34.6 miles per gallon.

This also was about 9 miles of motoring and I pedal sailed back.

The great thing about the TI is that you DONT need an outboard.. but this boat is also the swiss army knife of floating stuff.. so I wanted the option for a particular trip I want to take.

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 Post subject: Re: TI outboard mount
PostPosted: Fri Mar 27, 2015 12:44 pm 
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Joined: Wed Aug 06, 2014 5:52 pm
Posts: 26
Location: North carolina
Nice design. Ill copy your design but will use 8 inch geartrac with full backing plate. This way i can install something in geartrac when motor mount is off. Also good when time to sell. I have not done it yet so not sure if this is an improvement to your design or not. Comments from the experts please before i start this. My friend whose a welder olso promise to help so if you have any better design ideas for hobie ti outboard motor mount please share.


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 Post subject: Re: TI outboard mount
PostPosted: Sat Mar 28, 2015 8:04 am 
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Joined: Thu Jun 01, 2006 1:16 pm
Posts: 209
Location: Colorado
The geartrac looks like a good thing..

I put backing plates on the brackets I permantly installed but I think I could have backed off a little on what I did (however the backing plate adds very little weight so Im still glad to have them). There is hardly any force trying to pull the bracket off the boat (where the backing plates would come in handy). What I found is that its mostly rotation forces you have to deal with. I marked up the picture below to show this somewhat. The metal bracket going to the fishing rod holder handles the rotation caused by the outboard thrust but when the outboard is in the up position for sailing, its also a 30 pound weight that can swing forward so I had to add the line also shown in the picture to handle the rotation in the other direction. Those little posts really helped keep the outboard bracket from slipping when it tries to rotate. The eye strap to the rear also has a backing plate and maybe that one is important. The brackets mounted to the hull of course do a great job of limiting any rotation at all at the bottom of the motor mount. On the other side opposite of the outboard the attachment mostly just needs to hold the outboard bracket down but it also helps control the rotation.

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Being able to remove all of this is nice - a beny for the geartrac is that you can find other uses for it. I just took the TI out a couple days ago no motor.. really nice also to NOT have the motor..

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 Post subject: Re: TI outboard mount
PostPosted: Mon Mar 30, 2015 10:41 am 
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Joined: Wed Aug 06, 2014 5:52 pm
Posts: 26
Location: North carolina
Thanks for sharing your latest thoughts about your design and latest pictures showing how much youre enjoying your TI. Most of the time ill be using the 18 trust watersnake TM to help us lauch in a lake as my wife is not in good shape anymore to help me pedal. The outboard will be used only when we go out sailing in the ocean but thats probably just twice a year. Its good to know i can quickly come back when swells starts to scares me.
This outboard mount sketch i saw in the internet plus the 8 inch yakattack geartrac is my current idea of TI outboard mount.

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