fastest tow speed for inflatable boat and motor

[Rolf]

What is the fastest speed you can tow a 10 foot inflatable witha 59 pound motor attached? I have a tow harness clipped to its port and starboard tow rings which I am running to the aft port cleat of my 26x. Does this setup sound decent? Leaving for Catalina tomorrow morning..
Happy Turkey day,
Rolf

[mike]

I tow our dinghy with a nearly identical arrangement, though the motor stays on a bracket, not on the dinghy. But I've been wondering... is it ok to tow the dinghy with the motor attached, or is this asking for trouble? In other words, is there a substantial danger of the dinghy/motor being capsized during the tow, even if large beam seas and high winds are not present?

--Mike

[Duane Dunn, Allegro]

I found our dinghy towed really bad with the motor on it. I wouldn't want to go far doing it and would keep the speed under 10 knots.

With the motor (6hp) off and on the bracket on the mac the dinghy can be towed at any speed.

We also found that we lost over 1 knot of speed towing the dinghy and over 2 knots towing when the motor was on. We invested in a fast, high quality auto shut off air pump. With this we are much more willing to put the dinghy on the bow deflated and then re-inflate at the next stop.

[waternwaves]

hmmmm,

I know that a 9ft zodiac with a plywood floor, without the motor mounted, on a 6 ft bridle with a 50 ft painter, towed at 9mph, in 15-20 mph winds will flip when you hit a large wake from another boat. (the little outboard was not on it at the time)

I suspect any contrary 20 mph wind under half a dinghy will flip them...

Enjoy!!

All these 90's running around..... Santa.... I want my E-tec 90....

[Tom Root]

Rolf, I did post this before, but I will tell ya what works for me!

I made a bridle arraingement that starts around one end tube near the transom, run it up to your towing eye and give yourself about 6' or so slack, run it to the other tube and tie it off! It's that simple. You may have to lash it to the tubes so it doesn't creep off, but this must be done to pull the dinghy on a flater plane and so you don't rip out your towing eye! Just make sure they are running under the boat, lengthwise! Leave it on during operation, and use it as a painter.

I lash another line to the rear stay and use a quick clip to the loop/painter I just described. You pay out enough line to allow the dinghy to ride the crest of the second wake behind you. I have never experienced any problems whatsover doing this for many thousands of towing miles, and many years of several dinghy's/boats.

Of course when you get into close quarters, draw in the line to about 1 dinghy length away, and watch that you don't foul the prop.

Leave that motor attached, and make sure it is tight! I lock the screwdowns together, but tying them works also. Also ensure you lash ALL items securely in the boat while it is being towed, I even leave my gas tank in there! Try it and just play with the amount of line to get her from acting squirrely, turn your head around every 10 mins or so to assure yourself all is well, etc. I do this with a 10' Avon and 9.9, 4 stroke Honda right now.

You have a short tow...22 miles. I have towed from Oceanside to Catalina ....52 miles, 18 knots, with my trusty dinghy happily chasing me!

Oh, and Happy Triptophan day to you and yours!

[waternwaves]

Tom,

did I read that right??/
" lash another line to the rear stay" seems taht would slide up and down on the stainless hardware, and rub on the fiberglass......, am I missing something here....?

Thanks

|>

[BK]

I towed my 12 inflatable for 7 weeks in the N/W during 3 trips and also towed many trips to Catalina. I do 4000 RPM and let the inflatable ride on the 2nd wake. This is about 25 feet. I use a briddle and tie it onto just one rear cleat. This briddle is the only way to tow as the inflatable will swing back and forth using two lines (Thanks Steve). This requires a little experiment but I try to get the inflatable to ride down the 2nd wake so it has less drag. I leave the engine on at all times while towing as it would be too much bother at 55 lbs to remove. I also towed from Victoria to Friday Harbor in very high winds with the 8HP engine on. Where are you going to in Catalina? Its been cold, do you use a heater in the boat? I like Mr Olaf's ice cream in Avalon, he is on the water front, try some, he always has a long line.

[Captain Steve]

Like Bob, I tow behind the mac. I leave the 22 lb honda 2hp on it during the tow. Length of the towline is critical as Bob says it has to ride in the proper wake wave. I tie it off to the port rear stantion, and its handy to pull it up close quick when in port manuvering around into a slip.

[Rolf]

Thnx for all the quick replies, although I am still a bit confused as to whether or not to leave the motor on. BK, Olaf's is always a first stop, right after Antonio's for pizza, a burger, or their great fish and chips using a beer(I believe) batter. We'll be in front of Tuna Club if conditions are right. Leaving in 30 mins...
Rolf

[Tom Root]

Tom,

did I read that right??/
" lash another line to the rear stay" seems taht would slide up and down on the stainless hardware, and rub on the fiberglass......, am I missing something here....?

Thanks

|>

Yes, I simply lash it to the rear stay. I have not noticed any scratches or wear whatsover. I used the cheap soft line that Home Depot sells for $10.00 for 100' of 3/8"

Btw, others say it is alot of drag when towing, but again I feel there are three things which minimize drag while towing!

1. Ensure the boat is fully inflated to spec. I pump it up so that it is very hard, AFTER it is in the water, because of course the cold water contracts the molecules of air, and allows the boat to be partitially deflated which can hog the water and cause tremendous drag!

2. Improper loading when towing and having too much weight on the bow of the dinghy can cause it to actually take on water and cause massive drag. If towing with the motor attached have it tilted up and locked of course. Get all that weight on the transom or as close to it as possible and with the bridle lifting the bow while it is being pulled from the stern, the boat will almost plane at most speeds, reducing drag.

3. Proper tow line length can result in less drag considerably, as others have said, riding down the forward side of the second wake can give it an extra boost also. If it looks like it is pushing water over the bow, it is of course providing drag.

I have towed a 14' kayak on top of an 8' dinghy from Catalina also, and two Kayaks end to end with no problems. I rarely deflate/inflate to bring a dinghy on a passage, as even with a high volumn expensive 12V battery inflator, it seems a pain to do so. I have reversed over the painter a time or two resulting in fouling the prop, but that was because I was not paying attention when manuevering.

[Tom Spohn]

We have a 10'2" Zodiac Zoom with wood floor and inflatable keel. We tow it with the 6hp 4stroke Tohatsu attached and tilted up. A bridle is attached to the outboard forward tow rings. A floting line is attached to the bridle and runs to the port cleat. As speed increases it is necessary to play out the line keeping the dink on top of the wake. We have never had any problems at any speed as long as care is taken to keep the dink on the wave. Once the er knot that the Admiral tied it off with came loose and we had to circle back to retrieve it. This reminded us that there is quite a bit of pull on the line, and the Admiral has since been to knot tying class! Top speed was down by 3 or 4 knots, but no problems at any speed. We leave the motor on because it works OK and it is easier to put it on the dink in the Marina than from the stern of the Mac.

[Rolf]

Thanks for all these excellent replies, altho I only got to read most of them now. I used the bridle attached to two towing eyes lashed to my port rear cleat. Worked great with 57 pound motor attached on the way out, altho I had to lengthen tow line up to 50 feet before I was comfortable.

The thought of the dinghy flipping with motor on ( altho it never came close) also made me nervous going fast, so for journey home I hauled it off and stuck it on my starboard motor bracket. Pulling it off the dinghy was easier than expected, with me leaning on 90 tldi over well positioned rear of inflatable. I used the attached motor lifting straps, of course, for leverage.

A bad knot led to disconnection about 5 miles from home, but luckily I noticed a small fishing boat I had passed doing circles around something (My dinghy!) and I quickly returned and retrieved it.

My overall impression of towing was I rather not do it, at least on the way over to a destination. I'm more comfortable with everything tucked on board, so I can relax and completely enjoy the ride, altho towing back would be no big issue.

Rolf

[Rich Smith]

Have you ever seen those wireless child guard monitors (here's one: http://afgen.com/child1.html) Basically, if the childs electronic transmitter gets more than 50-100 feet away from the parent's receiver, an alarm goes off...It occurs to me that if you put the kid's transmitter in the dinghy, the alarm would go off if the dinghy broke free and drifted away...that would give you peace of mind without having to constantly check behind you.

I've used the same kind of thing for years for a man-overboard alarm...It's a product called Safety Turtle that includes a small bracelet that the kid wears...it's actually made for pools to warn of kids falling in but I use a 12v adapter and power it on the boat. I've attached the bracelets to my dog's lifejacket and the extra child lifejackets that I have on board...if one falls in the bracelet gets wet and the alarm goes off...I know it seems a little far fetched that you wouldn't notice someone falling in on a 26ft boat but I bought it more for when we're in port. It makes me feel better to have a snooze at the slip knowing that my dog has it on.

[BK]

Rolf, what does your starboard motor bracket look like? Is it on the stancion or like Duane's where it it a lift type? I would like to install one of these on the back of the boat to carry the engine on long hauls.

[Duane Dunn, Allegro]

Taking the motor off the dinghy greatly reduces the drag, particularly for a bigger motor. I could see leaving a 20lb 2hp Honda on, but not my 60lb 6hp Yamaha. Yet the little Honda is so light and easy to move why not pull it for better performance. Either way the line length must be adjusted depending on speed to get the dinghy riding up on the wake. I attach the bitter end of the to line to the starboard aft pulpit, then bring the line forward to the starboard aft cleat. It's easy to adjust the length there, no knots needed. In port or anchoring pull it in all the way and it will ride on the starboard hip with no worries about it or the line getting in the prop.

I think the key is to have a easy way to move the motor from the dinghy to the mac. For us this is the lifting arm we created by making use of our transom mounted mast carrier. It's quick and easy to move the motor. Having to wrestle it by hand would be much harder. Leaving it on the dinghy adds a lot of drag. Just hand hold the line at 10 knots with and without the motor and you will notice the difference with the motor on.

I also like the security of having the motor on the mac and the lowering bracket makes it available as backup power. My 6hp will move the mac at 6 knots.