You may have seen in another thread that I'm planning to use my ATV in challenging terrain.
The picture is halfway up looking down at the mild part of the hill.  It has similar topography & trees on top but it gets steep in between.
So I bought a crush protection device, a QuadGuard from New Zealand.  There were shipping issues but I eventually got it with no extra charges.
It attaches to the rear rack and as a strength check I grabbed that rack the way people pick up fallen cruiser bikes, hands behind my back and lifting with my legs.  My doc said I can't lift heavy things any more so that's pushing the limit but it saved me a lot of time figuring out another way to test the rack.  I managed to lift both rear wheels off the ground without any change to the rack at all.
The rack is attached to the frame in 4 places and once to each rear fender.  It's not massive but like I said, nothing changed lifting the ATV by the outsides of the rack.  The QuadGuard retaining bars fit well in places that are "indeterminate" as far as force distribution goes but again, it passed the lifting test.
I did a few things to my brand-new QuadGuard that may have voided the warranty but I thought necessary for mosquito control and to avoid stinging insect occupation in advance.  I drilled 1/8" weep holes in the 4 bottom corners to let water out.  They are #1 and #2 in the picture.  The 2 big holes would let most water out but some could stay if the ATV were on an incline.  Mosquitoes only need a little water to breed.  At #3 and #4 I covered the holes and top opening with some plastic bug screen held by all-purpose pvc/abs adhesive.  I haven't tested how strong the bond is but it feels good.  I've tried taping the screen to things but it is made of plastic that just doesn't stick to tape.
The QuadQuard attaches with 2 bars, 4 bolts, and hook-shaped clamps that fit over the CForce 400's rack bars.  The square bars are almost the same dimension across corners as the round bars are in diameter.  The torgue specified is 7 Nt-M or 62 Inch-pounds, about 5 foot-pounds.  It is not a lot of torque but it squishes the bottom of the QuadQuard until the bolts reach the bars, then it reaches full torque quickly.
The ATV looks good front & rear.  My way getting on & off is unaffected.

Hello kids,
I am thinking about buying a "roll bar" thing for my C-Force 400.
I'm 65 years old and I intend to use it in challenging terrain.
The interweb search turned up 2 units in New Zealand and 1 in Australia.
I didn't see any from USA or Europe.
I am thinking about this one at https://www.quadguard.co.nz/
It costs about $750 give or take currency and shipping Can't say
It's flexible shape is supposed to wrap around your body until the ATV weight is supported elsewhere.
It is basically 1 piece of urethane or other rubber compound that springs back to shape, or almost back to shape.
They say to replace it if it is badly damaged in use.
So the potential is there to be out another $750, and another, and so on.
There is a less rigid, more effective version costing $1500.
That one seems to be fully resistant to damage and has adjustable tension, and replaceable covers.
The Australian model is made of steel tubes and I think it might break some sensitive  parts but the transition is smooth so far.     
Your experience & advice is welcome, can't promise to follow it.                                                                                                                                                                                           

My right front amber reflector lens fell off its black plastic backing.
I tried double sided outdoor mounting tape that does a great job on some things but I couldn't trim it well enough to get contact on the various surfaces behind the lens.
It may have fallen off by itself since I couldn't see any adhesive on it and it didn't snap in.
It's more likely the sides of my trailer bumped it and knocked it off while loading or unloading (yep it's that tight).
In any case I'd like it to look as good as new since the pieces aren't scratched or broken.
I might try black silicone RTV if I have any.
I have crazy glue somewhere.
I have duco cement (plastic model glue).
Elmer's and gorilla glue are available.
I'd appreciate hearing what works before experimenting.
Thanks In Advance,
-Jim

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 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.

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.