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PostPosted: Sat Aug 19, 2017 7:05 pm 
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Pro10:
The prop I'm using is for a toatsu (or however the heck you spell it). I get mine from Iboats, you can get 6" pitch and 7" pitch, my TI with it's twin outboards maxes out at around 15mph. If I go any faster than 15 mph there is great risk of exploding my motors, (I've lost a couple motors over revving, which has nothing to do with rev limiters, (it's the water driving the props).
I'm not sure what your gear ratio is, (on the Honda 2.3 it's 2.43). If you look up on any of those on line prop calculators if you know your gear ratio you can calculate max speed at max rpm (wot). It's likely you a little short on HP to get to the 15mph with the 7" prop, (I'm thinkin you will need 10 hp maybe more), I get the extra hp from my wing, ( my engines only provide about half my hp requirements).
I recommend starting with the 6" pitch prop the move up to the 7 if you think it will work. They are only like $20 bucks, so their not goin to break the bank. I also have 10" pitch prop's that get me up to 20mph max, but I only used them with my foils. With the 6" prop I think you"ll hit 12mph max (probably only with sail and motor though in good wind)
If you have trouble finding them, PM me and I'll look up some old invoices if needed.
FE


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PostPosted: Sat Aug 19, 2017 7:50 pm 
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fusioneng wrote:
Pro10:
The prop I'm using is for a toatsu (or however the heck you spell it). I get mine from Iboats, you can get 6" pitch and 7" pitch, my TI with it's twin outboards maxes out at around 15mph. If I go any faster than 15 mph there is great risk of exploding my motors, (I've lost a couple motors over revving, which has nothing to do with rev limiters, (it's the water driving the props).
I'm not sure what your gear ratio is, (on the Honda 2.3 it's 2.43). If you look up on any of those on line prop calculators if you know your gear ratio you can calculate max speed at max rpm (wot). It's likely you a little short on HP to get to the 15mph with the 7" prop, (I'm thinkin you will need 10 hp maybe more), I get the extra hp from my wing, ( my engines only provide about half my hp requirements).
I recommend starting with the 6" pitch prop the move up to the 7 if you think it will work. They are only like $20 bucks, so their not goin to break the bank. I also have 10" pitch prop's that get me up to 20mph max, but I only used them with my foils. With the 6" prop I think you"ll hit 12mph max (probably only with sail and motor though in good wind)
If you have trouble finding them, PM me and I'll look up some old invoices if needed.
FE

The Tohatsu 3.5 HP motor came with the 7" prop which was the largest pitch that Tohatsu offered. I appreciate the advice but it's moot now that I returned the motor. Hopefully the Suzuki replacement will come well propped for the TI.


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PostPosted: Sun Aug 20, 2017 8:26 pm 
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Quote:
Pro10:
The prop I'm using is for a toatsu (or however the heck you spell it). I get mine from Iboats, you can get 6" pitch and 7" pitch, my TI with it's twin outboards maxes out at around 15mph. If I go any faster than 15 mph there is great risk of exploding my motors, (I've lost a couple motors over revving, which has nothing to do with rev limiters, (it's the water driving the props).
I'm not sure what your gear ratio is, (on the Honda 2.3 it's 2.43). If you look up on any of those on line prop calculators if you know your gear ratio you can calculate max speed at max rpm (wot). It's likely you a little short on HP to get to the 15mph with the 7" prop, (I'm thinkin you will need 10 hp maybe more), I get the extra hp from my wing, ( my engines only provide about half my hp requirements).
I recommend starting with the 6" pitch prop the move up to the 7 if you think it will work. They are only like $20 bucks, so their not goin to break the bank. I also have 10" pitch prop's that get me up to 20mph max, but I only used them with my foils. With the 6" prop I think you"ll hit 12mph max (probably only with sail and motor though in good wind)
If you have trouble finding them, PM me and I'll look up some old invoices if needed.
FE


FE, I think your selling us some Florida swamp land with the speeds you say you are achieving. I have looked at a bunch of your videos and the speeds you are seeing are about what the rest of us see (way less than claimed). This is your video and it looks like you are hitting around 9 to 10 mph. You can hear an outboard running in the video and you are pedal sailing. This is actually fairly close to what I get also.

https://www.youtube.com/watch?v=-npwA3izDiw This would seem to be the fastest video you have.

Your wing also just doesnt do much more than a regular jib does. I was into ice boat and land sailing for many years and we experimented with all sorts of double surface windsurfing sails and the "double surface" just doesn't really do that much. If it does anything, its only incremental. The only data I have seen on the forums from you was that it had a L/D of 40 which also said you had guessed on that number based on it looking twice as good as some other sail. No real evidence with a valid test is ever given and what you claim seems to be very much exaggerated based on all of my own experiences.

Quote:
If you look up on any of those on line prop calculators if you know your gear ratio you can calculate max speed at max rpm (wot)
FYI, this is not exactly correct. You have to know a target "slip" for your vessel at some speed to use the calculator. Somewhat complex to find what the slip for this hull is. I have measured it for a displacment sailboat hull.. its much different than what you would expect.

Anyhow, please prove me wrong.. You made this claim
Quote:
I also have 10" pitch prop's that get me up to 20mph max
How did you measure that, what were the conditions. .You must have made a video or taken a picture going that fast.. I like your posts.. but have a real hard time believing any of the claims presented..


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PostPosted: Mon Aug 21, 2017 7:36 am 
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I'm sure all the guys with the Hobie spinnaker kit can hit the same max downwind speeds I do in 20-25mph winds, (most spins are capable if 1=1 on downwind).
My TI has a bowsprit that angles the foresails so they also create a lot of upward lift. This raises the bow up out of the water a foot or so, (also prevents pitchpoling and diving which is a problem with these boats).
I only ever achieved any great speeds in downwind runs in higher winds. For example I would only ever put my hydrofoils on the boat if the winds were over 15mph because I could only get up on the foils when the boat was traveling faster than 8-9mph (which is hard to do with a TI, (that's the foiling speed I designed into the foils). This was all always downwind. As soon as the boat got any higher than 70-80 degrees (wind from the stern), the boat would drop off the foils. The reason for the ten inch pitch props was an attempt to try and extend my foiling ability so I could foil on a reach or slightly upwind. The theory was if the normal power range of the motors is 0-8 mph, by increasing the prop pitch I could move that useful power range of the motors up from 0-8 up to 12-20 mph. At any speed below 12mph the engines can't posiibly get up to full hp/rpm. BTW a normal 10" pitch prop is I think around 10" dia, and designed for a ten hp motor. My props are only 6" dia. And barely propel the boat at all if the only power source, ( I could barely get 6mph at WOT and the engines were no where near max rpm (simply not enough hp to drive the props). However once the boat got up to speed (via the sails), the motors got up to full rpm and provided some useful additional propulsion, (never primary propulsion).
I admit I used to be a hydroplane racer and motorhead, never much of a sail guy, (I get super bored going 4mph). I could have built custom engines I guess with the correct hp (around 15hp ea), but those type engines only have a life of a few hrs, so I did what I could with stock off the shelf outboards, (not much to work with out there commercially within the weight limitations of the boat).
On the days I would try to go out with my foils the only boats out on the water were trifoilers, (there are several around here). It seldom ended well, and I had several horrendous crashes. Most of this all occurred on my previous TI's between 3-7 yrs ago. I kind of figured out that this is not the type of boat to be doin that kind of stuff with.
Now fast forward to the last 3yrs all my efforts have been toward upwind power sailing, (tripower,,, thus most of my videos, I didn't get my gopro until 3 yrs ago). Anymore I don't go out at all in any winds over 7mph (I prefer nice flat water because of my bad back). With my current setup my average cruise speed is 8-10 mph ( in very light winds), and I get somewhere between 60-80 mpg with my locked throttles at low rpm. The motors alone with no sails and no peddling propel the boat to 7-8 mph on flat water at the low throttle setting, with just one engine in the water that speed is 5-6mph, (I sometimes keep one engine tilted up when I'm not in a rush to get anywhere). The video you are referring to the winds were 6-7 mph I was traveling upwind (with the wind 20 degrees off my bow), at around 9-10 mph with the throttles a little higher than normal (somewhere around 1/2 throttle (that's why the engines were very loud). Of course my normal great fuel economy went out the window that day. If the wind had been 10-12 mph The boat would have been traveling 10-12 mph on the same point of sail. However as the wind increases more (12-20 mph) I don't get any more speed upwind (12mph is about it), actually in winds 18-22 mph upwind speed gradually decreases, I'm lucky to get 8 mph forward speed in 22 mph wind, and the throttle has to go higher just to achieve that, (terrible fuel economy).
Now downwind is a totally different story. I have to jibe downwind (wind around 30-40 degrees off the stern).
This is where the prop pitch becomes extremely important, and where I have exploded a couple engines going over rpm, ( the water actually driving the prop, as if running the motor out of the water. In 10-12 mph downwind the boat travels around 10-12 mph. In 15mph and over downwind I run into my max speed limitation, (15mph), I have to back off on my speed in order to not explode my motors, (gets very expensive, just saying). Also at anything over 10 mph speed the boat is an extreme handful to operate, and not really designed to do so, basically something is going to break.
At lake Hartwell this summer we had a couple days of 22-25 mph winds. I snapped two wing sail masts in high winds , (fortunately I brought a spare mast along). After snapping the second mast, I was basically done sailing for the rest of the vacation (no more masts), all pretty foolish on my part really.
My TI has a reserve capacity option that I call 'get the heck out of dode mode', when a storm is coming in and the wind is kicking up, I open up my throttles to WOT and motor sail off the water to safety. Max speeds in fairly high winds (15mph wind) are 12mph upwind, and 15mph downwind, on a 90 degree reach I'm lucky to get ten mph, (which is the worst point of sail on my boat, and I try to avoid).
Also keep in mind my TI is heavily modified and hardened. The boat has been widened to almost 13ft wide, the AMA's are heavily re-enforced. The hull has been heavily modified to a planing hull design, all the underside openings (except 1 mirage drive in the front with eclipse flow 90 fins), and the bottom of the boat is covered with a hydrophobic coating
(To reduce drag). I only ever run the boat with the 33sqft wing on the front giving me what would be equivilant to 150 sq ft of sail area. With all three of my sails out I have around 250 sq ft of sail area in the air, (though I seldom use the spinnaker anymore). I do get it out once in a while if I have long down wind runs or I get the bug to go fast (a really bad habit).
Also keep in mind almost all my basic mods like the mast topper, bowsprit, original motor mount, super heavy duty tramps and spray skirts, are all 7 yrs old now and pretty much everything is at end of life now. I have done nothing new to the boat in the last couple three yrs except just use the boat as is.
Sure I had plans for a new main (furlable) wing sail, and even bought the fabric, (still sitting in the closet).
It was all fun for me figuring all the stuff out, and I had great fun doing it. However this is not the right boat to be doing all this stuff to. If you want a go fast super boat, get an f17 class cat, widen it, (somethin with 500 sq ft of sail), design yourself and build yourself a new type of furlable wing main sail, (nothing that has been done before), design and build your own foils for it, (some new design), then you really got something special.

I won't post anymore of my stuff ( too confusing to everyone).
FE


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PostPosted: Mon Aug 21, 2017 8:42 am 
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Quote:
The theory was if the normal power range of the motors is 0-8 mph, by increasing the prop pitch I could move that useful power range of the motors up from 0-8 up to 12-20 mph. At any speed below 12mph the engines can't posiibly get up to full hp/rpm.


You should measure RPM to know what is happening. A "theory" can be completely wrong and misleading but sure sound good. I can somewhat hear your outboard (or outboards) in that video and it sounds like they are getting up to the rated RPM. It takes more HP to get to higher speeds. You can not get more hp that the rated hp by increasing the pitch. That theory is just not correct. The Suzuki 2.5 definitely is getting close to the rated RPM at about 8 mph. It wont put out any more HP than 2.5 hp. The only way to make the boat go faster would be to actually decrease the pitch just a hair to get the RPM up closer to the RPM where the max HP is rated.

I still take it that you have never measured those high speeds like 15 to 20 mph since that was not mentioned. These must all be theoretical speeds?

FYI, you have a lot of very useful post and I appreciate your inventive nature. I just do a lot of grimacing when I see those really high numbers presented like you are actually achieving those speeds..


Last edited by walt on Mon Aug 21, 2017 8:54 am, edited 1 time in total.

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PostPosted: Mon Aug 21, 2017 8:52 am 
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FYI, my peak speeds on the TI has been around 12 mph and that was going mostly downwind using a barber hauler setup in some winds that definitely exceeded 12 mph but I dont know how much. I know this speed because I have a hand held Garmin GPS mounted to the round hatch just in front of me - easy to see and watch but far enough away that my arms dont mess with the sat view. I was actually watching the speed because you cant trust peak speed reading on a lot of GPS receivers. I actually have had the outboard on the boat going that fast but it was lifted out of the water - not running.

If I were going to really mess with the sail plan, I would go with a stayed rotating mast (a large carbon fiber foil shaped rotating mast would be really cool) and a non overlapping jib. But that gets away from what I really like about the TI - the super high easy to manage wind range.


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PostPosted: Mon Aug 21, 2017 5:59 pm 
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FE last post has a lot of interesting stuff in it and I think Im understanding why he increased the prop pitch. It seemed like the wrong thing to do but that is because I use the outboard way different than FE. I use the outboard to get somewhere reasonably fast. When I get there, I shut the outboard off and sail. Often its somewhat like a ski lift. FE on the other hand motor sails. The outboard is running the whole time he is moving. Since he has a secondary source of power (sail and pedal), he will have a cruising speed (like 9 to 10 mph in that video) that probably does benefit from a higher pitch prop.

I looked at my own case with the Suzuki 2.5 hp which I think is a nice match for how I use the TI.
Just the outboard itself and with just me in the back seat gets the TI up to about 8 mph at full throttle. I have not measured the RPM required for this speed but I am going to guess that its about 5000 RPM based on knowing what 6000 RPM sounds like.

I did calculate the prop slip for the TI at 8 mph and for 5000 RPM (prop pitch is 5.5 and gear ratio is 2.15). FYI, the equations used are from here http://www.go-fast.com/prop_slip.htm

The slip for the conditions above is about 35% and the prop theoretical “screw” speed is 12.35 mph. This means that at the pitch of the prop and at how fast it is rotating, the prop would screw through the water at 12.25 mph. Since the TI is traveling at 8 mph, this is how the prop generates thrust. Now if there is some other force was propelling the TI (such as the sails), the outboard could rev up to 6000 RPM which has a theoretical screw speed of 14.53 mph.

So my TI would need to be traveling greater than 14.53 mph before the water moving past the prop actually tried to spin it faster than the motor was trying to spin it. Well.. Im not at all worried about 14.52 mph.. pretty sure that will never happen while Im motoring or even motor sailing.

So currently my prop is pitched to give me close to 2.5 hp and I know that much power will drive the boat at 8 mph. In order to go faster than 8 mph, I would need to add additional HP say from the sails. If the TI follows a square law drag vs power, adding an additional 2.5 hp from the sails (for 5 total) gets the boat speed up an additional 2.8 mph for a peak speed of 10.8 mph.
But at 10.8 mph, my 5.5 pitch prop is now just letting the outboard rev limit. So I need to go to a higher pitch prop like FE has done in order for the outboard to still give 2.5 hp at those higher speeds.

There is of course a down side to this higher pitch prop. Say there is no wind or it is fairly light. The outboard is going to drive the boat and create an apparent wind.. and apparent wind can create lift. The problem is that the apparent wind for this condition is going to be almost directly head on. For the sail to create any lift, it must have an angle of attack and in this particular case of directly head on apparent wind, the sail lift force vector is actually pointing BACKWARDS – doing the same thing as drag.
You just cant get power out of sails in no wind and very little power out of sails in low winds. Ice boats are able to work with this as they have very low drag and don’t need much power to work. But the TI does.

Without the sail generating any power (which is the case for no wind or light wind), now that too high of pitch prop basically bogs the outboard down and since it needs RPM to generate HP, you would no longer be able to generate enough HP to get to 8 mph. In the case where I was motoring into a head wind, the too high of pitch prop would likely result in even lower peak speeds. In the no wind conditions, I actaully degraded my speed going to higher pitch.

In my case where I generally don’t motor sail, Im just trying to get some place where I want to sail (without the outboard running) as fast as possible, the Suzuki 2.5 hp with the 5.5 pitch stock prop is about perfect.

If you are often motor sailing and in strong enough winds where the sails are going to generate significant additional HP over the motor, you probably do need to go to a higher pitch and you probably can achieve some fairly high cruising speeds (like 9 to 10 mph, maybe more with two 2.3 hp outboards). But you also have the tradeoff of losing speed over the stock props when there is light wind, no wind or a head wind.


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PostPosted: Tue Aug 22, 2017 4:26 am 
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I think you understand now. One additional factor that I never anticipated is my wing sail design which is 6" thick (eppler 420 airfoil) is a symetric design (same shape on both sides, creates no lift at all when symetric, it's just a big weathervane, creating no lift whatsoever, and almost no drag), In order to switch automatically to it's assymetric shape (like a piper cub wing, (creating usable lift and organizing and aligning the air to the mainsail, ( the main provides all the power). The air has to have a bias, (creating vacuum on one side and pressure on the other side of the wing). This means the minimum airflow over the wing has to be a minimum of 6mph with biased air in order for the wing to do anything at all. This means I cannot sail directly into the wind ever. My forward motion (minimum 6mph) creates the apparent wind neccessary to make the wing change to it's assymetric form. So for example if the natural wind is coming at me nose on at say 5mph, you add together the forward motion (say 8mph plus the 5mph natural wind equals 13mph of usable air going over the wing). I have to create a bias with that air to make the wing change to it's assymetric shape so I have to turn off the wind slightly, usually 10-15 degrees off the wind is enough, this is enough pressure on one side of the wing and vacuum on the other to get the wing to go assymetric. The wing is not a sail, it's a power amplifier, (similar to how an air conditioner works, by taking existing energy and re-directing it into something useful). In this case it is aligning and accelerating the air over the back side of the main (creating a vacuum), thus forcing the main sail to do work, where it would normally be just flopping around like a wet noodle.
This is a totally different concept from anything in existance and very difficult to grasp apparently (basically my boat is not a sailboat, it's not powered by conventional means. In really really light winds ( 2-3 mph, I have to actually sail in an S pattern (constantly on a curve via rudder) in order to create any bias at all. In 2-3mph wind I doubt the wing adds more than 1mph to my speed. With the throttles always locked at a fixed low throttle setting (so the engines are nice and quiet) you can actually hear the rpms on the motors speeding up, (you know the power amplifier is doing work when the engine rpms increase).
Now the other extreme, lets say I'm traveling my normal 8mph and the wind coming at my nose is 12mph, that's 20mph of usable wind blowing on my face that I can align and amplify over the main sail, basically forcing it to do work that it normally wouldn't be able to do.
All this only works upwind or downwind, on a 90 degree reach ( which is my worst point of sail), the wing and the mainsail are only working as sails (not amplifiers), so everything reverts back to normal sailing rules (on the TI that's .6 windspeed). In amplifier mode I often hit 2x windspeed.
My normal VMG is always 8-10 mph upwind.
Downwind is a little different story, I have to be traveling faster than the wind in order do redirect apparent wind over the wind. So the closest I can sail downwind is around 30 to 40 degrees (wind off my stern). This is why whenever you look at any of my videos all the sails are always orientated exactly the same weather I'm running upwind or downwind. This also renders my spinnaker sails totally useless (even my wing spinnaker), because if I'm already running 2-2.5 x normal windspeed the spin totally collapses and becomes a giant airbrake, (oops, I didn't anticipate that one, that's the main reason the spin just hangs in the garage now).
The entire concept of what I have your not going to read about in any sailing theory manual, and is very difficult to grasp the physics. All I know is I get to go out every weekend and sail around at 8-10 mph, using about a buck in fuel (which I can easily afford). I could care less what the actual wind direction and speed is, (I don't even check anymore), and don't even bother checking the tides anymore, ( the tides around here are very strong ,(5-6mph) and with a stock TI it's totally impossible to get thru our passes from offshore against the tide), (been there done that many times), anymore I could care less what the tide is. The boat actually performs best in very light air, (which is 80% of the time here).
I wish I could explain it better, but I can't, I just use the darn thing, (haven't done crap to the boat in 2-3yrs, I just use it) it makes little difference to me if people understand it or not, I'm just trying to be kind attempting to explain how it all works, that's all.
FE
Edit: fact of the matter is I really don't need the engines at all. Each engine is currently outputting 3/4 hp, (at the throttle setting I set at). Me and another strong peddler can achieve all the exact same effects and speeds with no engines at all. Problem is we only go a half mile and we are both totally used up and exhausted. Fact of the matter is I'm not going to ever be able to grow giant leg muscles, (I'm really smart but no athlete by any stretch of anyones imagination, and never will be). I can produce with sustained leg power (over ten hrs) maybe 1/4 hp and that's all there is, I require the hybrid engines to provide the remainder until I can design an amplifier system that only requires 1/4 hp (x 2 ,(two peddlers), until that day comes, or I grow giant leg muscles I'm stuck with the hybrid motors, maybe some day I'll be able to convert to solar/battery electric, (still hoping for the giant leg muscles though, it's on my xmas list).


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PostPosted: Tue Aug 22, 2017 7:47 am 
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Quote:
The wing is not a sail, it's a power amplifier, (similar to how an air conditioner works, by taking existing energy and re-directing it into something useful). In this case it is aligning and accelerating the air over the back side of the main (creating a vacuum), thus forcing the main sail to do work, where it would normally be just flopping around like a wet noodle.
This is a totally different concept from anything in existance and very difficult to grasp apparently


You will have to add me to the list of people who find your explanation difficult to grasp.

You may have a nice Eppler foil shape on the jib working together with your main sail but they still have to follow the rules of physics.

Sails generate a force by accelerating a mass of air in a beneficial direction and if they dont drag any air along with the sail in that process, they do it efficiently.

If there is no wind or light wind and you use either human power or motors to create some boat speed, the apparent wind is going to be coming from directly where you are heading. Change your direction and the wind is still coming from directly where you are heading.

No matter what type of sail you have (or sets of sails), they must operate with an angle of attack to the aparent wind. That is in the math.. look up the equations for lift. When a sail creates lift by operating at an angle of attack to the wind, the lift vector is normal to the sail surface.

And.. if the apparent wind is always head on (because it is only created by your boat speed) the lift vector will always be pointing backwards - trying to slow you down.

Another way to look at this is that there is no energy in air that is not moving. You just can not extract any energy from that air by moving through it. If you think you can create apparent wind where there is no natural wind and extract engergy out of it other than what you put in by creating the apparent wind in the first place, your simply violating the laws of physics..

Now if the condition exist where the apparent wind comes in at an angle with respect to the direction you are traveling, you can extract energy out of the wind.. and that is how we sail. Even if your speed is higher than the natural wind speed you can extract some energy out of it (such as iceboats). But you must have natural wind in order to do this and cant sail directly into it.

(if you have to use an analogy such as an air conditioner to explain things.. you may not understand it yourself. Analogies can be very effectively used to mislead.. best to not use analogies to explain things)


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PostPosted: Wed Aug 23, 2017 11:24 am 
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I'm not tryin to hijack this thread (oops already did), so I will be brief.
You are probably correct in really light winds (around 3mph) the wing is not likely adding any propulsion effort of any kind. I'm probably wasting my time tryin to sail in an S pattern trying to get the wing biased to it's assymetric shape, and zig zagging back and forth. However doing this keeps the mainsail full and not luffing, so it looks good, but fact of the matter is if I have no sails at all the boat goes 7-8mph, and if I have the sails up it also goes 7-8mph, I'll probably give up on the zig zagging, really no point in such light winds. But it does make me feel good when the sails are full and all the tells are streaming back.
FE


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PostPosted: Wed Aug 23, 2017 11:34 pm 
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I have the Honda 2.3 hp on my TI. My motor mount is simular to yours but my mount is just behind the seat and on the port side. I used the same size aluminum bars as you; however, I added a wedge between the base plate and the first bar so that I have a 10 degree transom angle like most boats made for outboards. This allows the Honda to direct its thrust directly to the rear thus eliminating almost all rooster tail. Thanks for the very comprehensive report.


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PostPosted: Thu Aug 24, 2017 12:19 pm 
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CobraIP wrote:
I have the Honda 2.3 hp on my TI. My motor mount is simular to yours but my mount is just behind the seat and on the port side. I used the same size aluminum bars as you; however, I added a wedge between the base plate and the first bar so that I have a 10 degree transom angle like most boats made for outboards. This allows the Honda to direct its thrust directly to the rear thus eliminating almost all rooster tail. Thanks for the very comprehensive report.


Any chance of posting a picture CobraIP?? I'd love to see some close ups... :)

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PostPosted: Thu Aug 24, 2017 1:03 pm 
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CobraIP wrote:
I have the Honda 2.3 hp on my TI. My motor mount is simular to yours but my mount is just behind the seat and on the port side. I used the same size aluminum bars as you; however, I added a wedge between the base plate and the first bar so that I have a 10 degree transom angle like most boats made for outboards. This allows the Honda to direct its thrust directly to the rear thus eliminating almost all rooster tail. Thanks for the very comprehensive report.

That is a very good idea, I will incorporate a 10 degree wedge into my design as well to offset the outboard motor manufacturer's expectation of a typical transom angle. Great observation.


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PostPosted: Thu Aug 24, 2017 7:24 pm 
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You may want to consider moving you outboard to the port side as well. This moves the tiller arm a comfortable distance out so you don't have to twist around to control the motor. Good luck.


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PostPosted: Thu Aug 24, 2017 9:26 pm 
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CobraIP wrote:
I have the Honda 2.3 hp on my TI. My motor mount is simular to yours but my mount is just behind the seat and on the port side. I used the same size aluminum bars as you; however, I added a wedge between the base plate and the first bar so that I have a 10 degree transom angle like most boats made for outboards. This allows the Honda to direct its thrust directly to the rear thus eliminating almost all rooster tail. Thanks for the very comprehensive report.



Can you please post up some photos?


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