Motor Advice

Topics primarily or specifically about the DS1. Many topics are of general interest, so please use forum sections on Rigging, Sails, etc. where appropriate.

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Motor Advice

Postby ksimolo » Sat Aug 11, 2018 12:20 am

I have read lots of posts about what size motor to put on a daysailer. The answers vary quite a bit but people's sailing conditions and skill also varies quite a bit. To give as much information as I can think of: We are new to sailing and have a 16’ 9” Spindrift Daysailer which is a slightly modified O’Day DS1. We sail on the Finger Lakes in areas that are 1 mile or less in width and surrounded by hills. Most of the time, the wind runs up the length of the lake. The launch is at the South end so most days we have to sail against the wind to get back to the launch. We sail for fun, not for how fast we can go.

Last year while sailing, an unforecast strong wind came up creating quite a bit of chop. The wind was so strong that we needed to reef the sail and try to sail back to the launch. We spent 3 hours tacking into the wind and gained a total of about 150’ even with sometimes trying to also run the 55 lb thrust electric motor. Eventually we had to get towed in by some nice people who said they had to tow in other sail boats and that the previous year they had the same problem when sailing. If the lake had been wider than 3/4 of a mile at that point, we might have been able to do better.

Do people feel that a Tohatsu 3.5 HP with I assuime a 20” shaft would be enough to fight the wind and larger waves we were experiencing or should we be looking at the 4 or 5 HP? The 3.5 HP would weigh about the same as the marine battery and electric motor we are using. I will give some specs:

3.5 HP 85.5 cc engine, 41 lbs, Forward and Neutral $1214 list

4 HP 123 cc engine, 57 lbs, Forward - Neutral - Reverse $1424 list

5 HP 123 cc engine, 55 lbs, Forward - Neutral - Reverse, Remote Fuel Tank (which is why I assume it weighs less) $1663 list

Any advice from your experiences would be appreciated.


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Re: Motor Advice

Postby 109jb » Sat Aug 11, 2018 2:42 pm

A 55 lb thrust trolling motor is equivalent to about 3/4 horsepower. Haven't put a motor on my DS yet, but maybe that will help you decide.
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Re: Motor Advice

Postby jalmeida51 » Sat Aug 11, 2018 3:22 pm

I use a 2.5 H.P. Yamaha long shaft and it pushes my Daysailer 1 through the chop and slop of Charlotte Harbor, Fl. with no problem. I t weights 29 lbs., internal gas tank, no reverse only forward and neutral. It took a little time to get used to rotating the engine 180 degrees to back out of the slip. I never have used more than half throttle to power through the chop. I bought it about 6 months ago and paid $920.00.
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Re: Motor Advice

Postby GreenLake » Sat Aug 11, 2018 5:51 pm

When comparing the weight of a gasoline motor to an electric one -- the difference is that you can use a longer cable with the electric one and move the batteries to the middle of the cuddy, where you want the weight.

You definitely don't want the same weight at the end of the transom, which speaks for having the lightest motor there that does the job.

Electric isn't quite there yet, when it comes to pushing through chop or going long distances. Trolling motors are older technology and rather inefficient. Modern electric outboards can deliver the same speeds for about a third of the electric power consumed. Yes, I know, that ratio sounds unbelievable, but I've tested a motor that performs better than my 40# trolling motor at 1/3 the power consumption per knot of speed.

Some of what's on the market is low power, optimizing the range you get out of a given battery. Such motors are worth considering if you largely need to cross patches of calm water. For example, I regularly do 6-7nm of which I've seen up to almost 50% becalmed. That's something that a trolling motor would just about be able to do (with two batteries) and one the modern electric ones does the same with 6.4 lbs of battery . . .

For areas with strong currents or chop, or longer trips, a gasoline outboard (or a propane one) can't be beat. For the DS, 2.5 HP should be sufficient. It should be enough to drive the boat to hull speed in flat water and the earlier reply here gives you positive testimonial for chop.

I've used a propane motor on a friend's DS. The absence of exhaust smells and the extremely non-messy fuel would be a plus from my perspective. The motor used was a Lehr 2.5HP and used the green propane cartridges; throwing an extra cartridge in the boat in case you use up the first one (about 1 hr) is the easiest thing, and we used the same supply of bottles to provide camp stove fuel.

Lack of a reverse is something to get used to. I did not do too well with it on my first try - it probably takes real practice.

With a propane cartridge inserted, the motor is self-contained: no external tank and no fuel line. Weight about the same as similar gasoline motors. (If you want to get really light weight motors, you'd have to go electric, and some are featherweights compared to trolling motors, let alone gasoline/propane outboards.
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Re: Motor Advice

Postby ksimolo » Sun Aug 12, 2018 2:28 am

Thanks for all of the information so far. I find it very helpful. The Tohatsu 2.5 is basically a detuned 3.5 and weighs the same as the 3.5 so I am not considering the 2.5. Yamaha's 2.5 is only 4 lbs less than the Tohatsu 3.5. I looked at the Leer's last year because I like the idea of propane but they had reliability issues. I was not looking at 2 strokes due to noise and they are banned in some areas. The electric outboards are nice but they are pricey, not as strong, and surprisingly had more reliability issues than I would have expected.

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Re: Motor Advice

Postby K.C. Walker » Thu Oct 04, 2018 12:43 pm

You may have already purchased a motor. However, I wanted to add that this summer I purchased a "sailboat prop" for my Evinrude twin cylinder 3 horse. It's a power prop and made of aluminum instead of the original plastic. The power to the water changed dramatically! I rarely need more than 1/4-1/3 throttle for hull speed. In flatwater and lightly loaded the boat planes at full throttle.
KC Walker, DS 1 #7002
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