This is the remote fob using its built-in clip to attach to the standard key.
(I put a little red on the key in case internet wizards could make a copy from a picture)
The manual is there just because I was looking for instructions on the plastics.
The blue shape in the background is a garbage can lid, nothing cooler than that.

Sorry, a bit more, the winch came with boots to cover the wire connectors on the motor but I forgot to put them on.
I will do it soon, though.
And it's nice that the ATV can now winch itself onto the trailer, should be less stuff to pack next time.

Installed the winch harness etc.
I swapped the red & black leads, noticing that one winch lug has a red boss around it, so I could have put the red wire there in the first place.  I cable tied the control box to the structure that holds the fairlead.  I tried to set the box so the wires would not guide water into the box.  Then I fed the 2 wires back and cable tied them.

I took the front center panel off, it covers the coolant cap and a fuse box.
The instructions as I recall said pry up something somewhere.
The actual procedure is to pry up the front bottom near the CFMoto logo to get a stud out of a grommet, then slide the rest of the cover towards the rear to unhook some plastic lugs.  After they are free the cover can be lifted up and away from the hold-downs.
I broke 1 lug off and bent the next.

My 2021 CF400S has about 0.5 hours on it and I put on a winch.  Getting the plastics off for the wiring was a lesson.
First thing, getting the left panel off.  It says remove the obvious screw I could see plus 2 screws inside the left fender.
I took out a few other screws but eventually figured out where the important 2 were.
This is the left front wheel well, by the way.

I'm moving slow on this, I know, but after putting a new floor in my trailer I wired the winch temporarily to a battery on the front rack using minimum nylon cable ties.  The short leads are on the winch side of the box so the box will almost certainly end up in the front wheel well.   It easily pulled the CF400 onto the tilted trailer and the fob control worked perfectly (except I'll have to swap the motor leads to un-swap the IN-OUT buttons).  The older portable-ish 5000 pound winch I was using on the trailer used a wired IN-OUT pendant that took some planning and added excitement if I tripped on it or accidentally pulled the plug out.
During the test install I didn't check the box for Motor - Battery markings (I assumed the long leads would go to the winch... wrong) and when I touched the battery with the motor-side leads I got the flash of a short circuit.  It was brief and didn't hurt anything but you'll want to pay attention to the markings on the box then connect the motor properly the first time.

The bad thing that happened, though, is I found the right front amber reflector plastic on the ground.  I doesn't snap in, or doesn't snap in anymore, so I expect to super glue it back on its hardware.

I wish it wasn't off balance but pics in the 500 manual look a lot like this setup.
Looked at the wiring & remote, super easy.
I only have to find a place to mount the box and wire-tie the 2 cables to the frame.
I think I want a cut-off switch, though, between the battery & the breaker.
The good thing is there aren't any connections to the ATV wiring so I don't have to worry that it might be canbus or tapping into the wrong circuit, or mounting a switch on the dash or handlebar.

I put my winch on.  It looks a lot like the factory winch on a 5 or 600 I saw on youtube.
If you see these pics (downsized a little bit for frugality) the 1st one is the parts on a tarp.
From bottom up in the 1st pic:
1. Fairlead holes have been slotted to the edges with a bias to the top so it will fit under a lip on the CF400's mount.
    A pair of rectangular 'dog' washers have a short leg each so they can straddle the edge of the fairlead's mounting plate.
2. The bottom bracket is the one the washers were cut from.  I had to round-file some holes into slots so they would be centered on my template/pattern.
3. The HF / Badlands winch holes were smaller than 3/8" so I drilled them out.  M8 or 5/16" would have fit clear.
4. The top bracket has more metal and the top of the drum lines up with the fairlead so it can use it.
2nd pic: Fairlead installed without pulling the plastic.
3rd pic: Turned out that both top & bottom legs on the angle iron brackets needed to face forward.  That made the locations of the winch mounting holes critical because it had to fit between the upper & lower legs with everything tight.  It did.
4th pic: This is what the CFMoto winch mount looks like through the fairlead mount area.
5th pic: The winch is mounted, plastics removed.  I also lowered the front of the bottom skid plastic temporarily to get wrench room.
6th pic: Plastic is back on and it's waiting for wiring.  I think I'll make a plastic cover/protector out of a plastic coffee can and duct tape, but that's later.
Now to search for wiring guides.  It's remote controlled by a fob so it should be simpler, but I'd like to do a quality job on the power.

It could be a long time before it hits even the 10 hour mark.
I may have to do an oil change just because time went by in an outdoor-equivalent temperature xone.
I might enlist a friend or acquaintance to drive the thing up and down my short gravel road for some of the break-in time.
In that case I'd like to let them do what they want with the throttle, and so I would like to have it pegged.
I wrote the original setting distance in the owner's manual.
I'll put it back when it is time.
But I do appreciate your opinion, NMKawierider.
This is the first time I ever had a throttle peg that wasn't caused by improperly installed linkage.
But that's another story for a different day.

I have a brand-new CF400 and the owner's manual says there is a break-in period before the machine can be used normally without voiding the warranty.
It says to operate below half throttle for 10 hours then below 3/4 throttle for another 10 hours, then do an oil change.
It also says I can't tow or carry loads during the break-in period.

Being a goody-2-shoes I wanted to set the throttle limiter at a point where it couldn't void the warrantee.
It comes from the factory set at maximum, the manual says.
It is a phillips machine screw on the right handlebar with an 8mm lock nut.
The setting is supposed to be the distance under the head, according to the illustration in the book.
Mine came set to 0.722" with a paint mark to show if it moved (or was moved).
So I thought 0.361" would be half throttle.
I unloaded the 400 by gravity from a tilt trailer backed up a slight hill, maybe 5 or 10 degrees of slope.
I set the "peg", as we used to call such things, at 0.361", started it, put it in reverse, and gave it what it had.
It didn't move.
I thought the peg is not a simple half thing and loosed it another 4 threads.
I had ridden the 400 in small circles in my back yard at home so I knew it could go both forward and backward slowly. at least.
The 4 threads gave it enough power to back up and operate like it should.
I ran it about a half hour, hit 10 mph downhill and almost that going up when it warmed up.
Later I thought the throttle cable is likely connected to a butterfly in the throttle body.
In that case with full throttle turning the butterfly 90 degrees, half the distance was probably 45 degrees.
When the butterfly disc turns it forms an ellipse that blocks the air coming in.
The area blocked is proportional to the cosine of the throttle angle.
45 degrees blocks 0.707 of the area so throttle of 45 degrees might be .293 percent of max.
I wanted .50 of max so the cosine of the angle should be 0.50 and the angle would be 60 degrees.
60 degrees is 2/3 of 90 degrees so I expect the best distance under the screw head to be 2/3 * .722 or 0.481"
Today I measured it and had to open it a little more to get 0.481" but a little more throttle will be nice to have.
9-1/2 hours to go before the next setting.

I just measured my 2021 400 to fit a Harbor Freight winch on it.
The winch mount on the ATV has 4 holes with centers making a rectangle 9-3/8" wide by 2-3/16" high.
The winch holes are smaller than 7/16" diameter, bigger than 27/64" diameter, therefore close to 11mm diameter, not threaded.
The fairlead mount has 2 holes about 4-15/16" apart, close to 125mm center to center.
Those holes have threaded inserts that fit standard M10 bolts.

The Harbor Freight 2500 pound winch has only 2 holes 2-15/16" apart, vertically near the centerline of the drum.
The HF fairlead holes are closer together than the CF Moto mount, maybe they are 120mm apart.
I think I can cut slots from the edge of the HF fairlead plate to its holes and make a custom washer to hold it.
I bought 1-1/2 by 3/16 angle-iron. I'm planning to crop 2 angles to fit into the 5-3/4" gap between the CF mounts.
I'll post again when I know how it works.

Thank you for the welcomes.  I'm going to check out the 400 section now.
I haven't got so far as to look at the air filter yet, it took some effort to figure out how to check the oil.
Maybe the owner's manual has that but I didn't see it, it's just on the pre-ride check list.

Hello!  I bought a CF 400S as my first real ATV, likely my only ATV.  I've had motorcycles but none were off-road bikes.
I live on 1/4 acre in the suburbs and have 8.5 acres 2-1/2 hours away.  The 400 doesn't overload my Northern Tool folding trailer so I didn't have to buy a trailer to buy the ATV.  I especially like the 4 wheel drive and fuel injection.  I need the ATV to climb a hill and push snow around, I hope it will do that.  I have some ideas if it doesn't.
No picture yet, sorry, it looks like a CF 500 with smaller wheels.