I asked the same thing at Gander Mtn when I bought my Minn Kota Endura 36# last fall. They looked at me like I was from another planet, and asked why I wouldn't just direct wire it to the battery. I said "because I don't want to be back here next week looking for a repair or a new motor". They insisted that they've always direct wired and never had a problem. Apparently, they don't power through 8 inch deep muck and blow up motors like we do, or they assume that the occasional smoked motor is just a fact of life, and that it can't be prevented.

I decided to figure it out myself, so I would simply need the current draw of the motor in question when under maximum load and then multiply by 1.25 to keep the draw under 80%of the rating of the wire and fuse (it's a reciprocal thing ). No dice. Apparently 'current draw' is notpart ofthe lingo of most troller users since all I could find listed was 'pounds of thrust' and 'estimated run time'. [:@]

OK, it was time to fall back and punt. I just used the wire size that was pre-wired to the troller as a guide (which meant opening up the motor's box in the store). It had 10 gauge wire (not marked of course like any normal wire would be -I had togo getwire strippers from my car to check the size [:@]). OK, I know 10 gauge wire is good for 30 amps, soI asked for a fuse holder and a small box of 30 amp 1-1/4" fuses for spares. I found them myself before the guys were even done discussing what isle theyMIGHT be in IF they had any.

The short answer is...
-find out the current draw and multiply by 1.25
OR
-measure the factory wire size, and use that as a guide
>14 gauge = 15 amps
>12 gauge = 20 amps
>10 gauge = 30 amps
OR
-call the manufacturer and ask them to recommend one.
(Hope they dont' say "why wouldn't you just keep blowing up your motor and put my kids through college by continuing to buy new motors and parts.")