Trailering a sib aft forward

lachancp

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Jul 24, 2021
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I was just setting up my 12.5 Zodiac mk2c to trailer with engine on the transom. Looking at the weight distribution I am heavy on the back end of the trailer making the tongue lighter and much more unstable. Trying to get ideas on a fix such as weight distribution , carry water ballast and such. came across a pic with the sib being trailered in reverse from conventional trailer where the bow is a the back of the trailer and the stern with outboard is just behind the tow vehicle resulting in a 60/40 towing ratio. I was wondering if anybody had experience with this and would love to hear your comments.
I do not think it would impose launching problems. This would be a great towing solution to ensure a stable setup than conventional.
 

Sea Rider

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Sep 20, 2008
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Welcome to Iboats.

Is it possible to play, move the wheel's axis to better balance the weight distribution on the tongue, or it's fixed ?

Happy Boating

 

lachancp

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Jul 24, 2021
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Trailer is a 8ft x 5ft ATV trailer foldable, I think I can since it came completly disassembled. I would have to double check. If I did move axle more to the end of the trailer where the outboard would be , the axle would have to be placed right at the end of the trailer, since it's a 12ft boat on a 8 ft trailer. Outboard is a 108lb honda 9.9 ,the zodiac is 170lb.Not much room to play with if trying to position the axle under the motor and transom where all the weight is. Right now with the bow facing the back the outboard is half way between the tongue and axle with it tilted in the up position. Looks nicely balanced , Just wondering if any problems launching and loading with bow facing the water. The first problem I encountered was trailer lighting. I use a set of towing trailer lights on a stick that I bolt to the transom. now I have to figure out how to mount them on the bow since the boat is now completly turned around.
 

Sea Rider

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If you plan towing the combo with installed motor, what type of support will the tubes be resting on ? as a 4 stroke motor is bit heavy will need to inflate both side tubes to their full air pressure factory stated or the transom will be bouncing which is bad for the adjacent glued parts.

Happy Boating
 

lachancp

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Jul 24, 2021
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Tubes are resting on 2x6x8 carpeted bunks on each side of the trailer. The transom sits on two 4x4 posts with a carpeted 2x4 aprox 6 inches across like a T figure on each end close to the tubes. Center is a 4x4 post with 2x4 T figure right under the jack plate. All three post sit in 4x4 post Deck support attached directly to the plywood deck attached to the trailer frame. With tubes inflated to pressure it raises above the transom supports, when tubes are deflated a little the transom sits directly on the supports which is then strapped tight the trailer frame. I'll post a couple of pics.
 

lachancp

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Jul 24, 2021
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Pics, Went for a run last night , trailer was quite stable. Outboard slides on its friction plate so needs to be tied down on its side. Lights need another attachment point in the center bar to the rear, wind pushes it over.
 

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Sea Rider

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Congrats nice transport, the combo is launched and retrieved from the rear whether at a beach, boat ramp ? That's a L shaft motor and a S transom, installed a jack plate to rise the motor as the lower leg was sitting to low and having water splashes out/in transom ?

Happy Boating
 

lachancp

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Jul 24, 2021
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Yes , with the trailer in the water I just push the Zodiac off bow first. When loading back on I just pull it back up on to the trailer by grabbing the transom and outboard with the short trailer you have to disconnect from the car put a rope on the trailer and car hitch then push the trailer into the water using the hitch like a pulley. I need to work on sending the trailer down the boat ramp a little more to get better control. coming out is easy enough the long rope tied to trailer and hitch it seams to work o.k. Note third wheel is installed on the trailers A frame so it can be maneuverable. L shaft on the motor since it was on my sailboat . I bought it new about 2 years previous of selling the sailboat. So I said I will use it on the Zodiac with a jack plate. Had to get a new prop , previous one was a power thrust. With the 9.9 setup this way I can get on plane not much splashing. It would be better with a short shaft 15 or 20hp on the back, but like I said it was brand new outboard.
 

Sea Rider

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Set if possible the motor height for the water flow to skim right under the small upper plate when on plane, for that purpose sit a boater up front, trim the motor to 90 deg and have a visual look at which lower leg is the water flow passing now, can prop right that motor as loaded with 3 blades less pitch props to run towards its mas wot rpm range factory stated, will need to install an induction tach for that and take the max out of that 9.9 motor.

Happy Boating
 

GA_Boater

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@lachancp

Keep it simple and write up another post with more pictures. Deleting post #6 makes the following posts nonsensical.
 

lachancp

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Jul 24, 2021
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Set if possible the motor height for the water flow to skim right under the small upper plate when on plane, for that purpose sit a boater up front, trim the motor to 90 deg and have a visual look at which lower leg is the water flow passing now, can prop right that motor as loaded with 3 blades less pitch props to run towards its mas wot rpm range factory stated, will need to install an induction tach for that and take the max out of that 9.9 motor.

Happy Boating
So are you saying I could lower the jack plate, so the next time I go out and go on plane , when I look down at the prop I should just see the first small set of fins just level with the water line ? I don't understand your last paragraph very clearly , I know there is a procedure to check your max rpm while running the motor with wot
I don't remember much about it , I would have to look it up again.
 

Sea Rider

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In reality don't know if need to raise or lower the motor to accomplish for the water flow, water line to skim under the upper small plate, water tests will determine so. Run a wot water test and report at which lower leg's plate is the water flow passing once on plane at that current motor height.

All motor must run inside their min-max wide open throttle (wot) rpm factory stated. Being a 9.9 a bit underpowered motor will have to make it run ideally towards it's max wot rpm range to get the max out of it, for that task must install an induction tach to check the wot rpm out at full throttle...

Happy Boating
 
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lachancp

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Jul 24, 2021
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I understand now , thanks. My spec RPM for a honda is 9.9 hp @ 5,500 RPM range between 5k and 6k. I look for the induction rpm meter that will work , I believe I saw a tach that fits the tiller handle then connects near the spark induction coil. I will look again.
 

Sea Rider

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I understand now , thanks. My spec RPM for a honda is 9.9 hp @ 5,500 RPM range between 5k and 6k. I look for the induction rpm meter that will work , I believe I saw a tach that fits the tiller handle then connects near the spark induction coil. I will look again.
Would recommend this particular brand and model : Hardline HR-8061-2, check IBoats, Amazon. Install it as per specs...

Happy Boating
 

Sea Rider

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It's on it's way. Thanks again
You can bolt the tach near the throttle grip to check rpms more closely.

3-Tach & Tiller Extender.JPG
If wanting to distribute more weight forward when solo boating can add a short tiller extender to help the Sib to plane faster..

Happy Boating
 
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