I am purchasing my first boat next week (Kenner Vision 1800, 115 Optimax). I will probably go with the Minnkota Riptide bow-mount. My questions are: how much thrust is needed to move this size boat, and what length shaft would work best. I'll be mostly fishing N. Texas lakes and maybe 1 or 2 trips to the coast. Thanks in advance.

I have a 21 ft Fishmaster CC and have a 80 lb riptide. I fish open water most of the time and 80 lbs is okay but when the wind gets up I could use a little more. 80 lbs will probably work great for your 18 footer.

Make sure you get a long enough shaft. Again, if you fish open water, the longer the shaft the better. You can always adjust the length shorter but you can't go longer if there's not enough shaft. Keeps the blow outs to a minimum in the chop. I have a 63" shaft and have no trouble with blow outs. I had a 52" on a similar boat worked great on calm days but it was too short in heavy chop.

One more suggestion, get the Riptide with Autopilot. I have that feature on mine and really like it. Reduces the amount of effort constantly adjusting the TM.

You probably want a 24V 65lb or better trolling motor for that boat. Shaft length of about 50 inches. You want a shaft long enough that the motor will not come out of the water in some chop. The dealer can probably advise you best on shaft length, but I would not go below 50" for that boat.

I have an 18ft Tracker TV18 and have a 24V 70lb thrust with a 45" shaft that does a nice job. It originally had a 12V 48lb and that struggled in anything over about 10mph wind.

I have a 74lb Minn Kota on my 17.5 ft Ranger. Plenty good for me and a 70 or 80 lb thrust sill do the trick for you. Get only a 24v motor and the batteries will hold all day.

The bigger the better. I would buy the 105lb thrust TM myself. You can never have to much trolling motor.

Thanks for all the replies. One more question, since this is my first boat. I assume that if I get a 24V TM, I'll need 2 batteries, or 3 if I go with a 36V TM. Is this correct?

kingwoodranger

i personally only have a 15 foot modified v boat with a 25 h yamaha and when i was looking for a trolling motor. i had guys telling me at cabelas 32 lbs will be enough. well i got a 46 minn kota vector. when you have it on 5 there is a wake behing me. but i am with you you can never have enough power.

yes MBradford

and i would go with about 74 lbs thrust and around a 50 to 55 inch shaft. 24 volt.

Hell you could probably ski behind that , we have 84 lb MG on a 21' Skeeter and never had any issues with pulling us around. Not trying to change your mind but you may check with Bob at South West parts on your TM, good folks over their.

Marc

lets stop the guessing..


How much thrust do I need?

In general you want to have as much thrust as possible for the times when you run into wind and current. The rule of thumb in choosing thrust is to take the total weight of the loaded boat and divide it by 70. For example, if your boat with people and gear weighs a total of 3500 lbs you will then divide that by 70. That means that ideally you should have a motor with at least 50 lbs. of thrust.

Motor Thrust Total Weight
30 lbs 2100 lbs
36 lbs 2520 lbs
40 lbs 2800 lbs
42 lbs 2940 lbs
44 lbs 3080 lbs
48 lbs 3360 lbs
50 lbs 3500 lbs
55 lbs 3850 lbs
65 lbs 4550 lbs
74 lbs 5180 lbs
101 lbs 7070 lbs


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Shaft length
If you want a bow mounted motor then you take the length from the top of the bow (where the motor would be mounted) to the waterline when the boat is loaded. You then add 20 inches to that number and then round up to the next longest shaft if you have to. So, if the distance from the bow to the water is 15 inches then you will add 20 inches to that. You come up with 35 inches but find that there is no motor for the brand you want with a 35 inch shaft. Therefore, all you have to do is round up to the 36 inch shaft. Simple, right?

Bow to Waterline Shaft Length
0-10 inches 30 inches
11-16 inches 36 inches
17-22 inches 42 inches
23-30 inches 50 inches
31-34 inches 54 inches


This came from Minn Kota site.
But as everyones says---more is better

50 lbs wont cut it in a wind on that boat. I know that boat well....and in a strong tidal current or a 5 knot wind, 50 isnt going to cut it. Bigger is better...and look at it this way: Once you have that Vision for a while and do some saltwater fishing, you'll eventually want to move up to the 21 footer. ( trust me..I know this first hand). You can take a 100+ lb trolling motor and move it to the 21. If I am wrong, you have only spent a few more dollars, but you can haul A$$ against a tidal current with it on that 1800.

Congrats on your new Kenner ! You'll love it !

I had a 55 lb on my 17.5 and it would not hold long enough in the wind so I upgraded to the 74. Take it or leave it but that was my experience.

I was looking into the same thing a few months ago. I searched all over and what I found was, bigger is definitely better. Also, if you go to 36 volt the amp draw is lower thus keeping you on the water longer. The higher ft/lb you go with, the less power you have to use in higher winds/current. Go with the biggest you can afford. Remember, a 101 ft/lb at 75% power is roughly the same as an 82 at 100%....Longer battery life per charge, longer fishing in high wind/current. Info provided to me by Boris Marine.