[Arizona Bushman]

Having to watch my budget, I couldn't afford to get a snorkel kit. What I did was build my own from items found at Home Depot or Lowe's. The total cost for the engine and cvt intake together was around $50 or less and is quite effective. I produced two short videos on YouTube to basically show how I did this. My YouTube channel is "cowdog64". Feel free to contact me with questions regarding this.

[Diver]

nice

[EZ Rider]

Nicely done and it looks like a fairly easy mod, but I have to ask...
Do you regularly get into water deep enough to flood the existing intake height?  If so, you play a lot harder than I do!   

Seriously though, We need to ride together sometime just to see if I can keep up with you!

[cr2crf]

Do you regularly get into water deep enough to flood the existing intake height?

A lot of folks do this to get the intake away from the dust.  Higher is better.  haven't done it yet but will be starting on it soon as my dealer says it won't void the warranty.

[EZ Rider]

Ok, That makes sense.  In that case, I took the panel off to look into doing the mod. 

Funny thing, there is a sticker between the seats that says "WARNING  Air Filter Inlet Grill. DO NOT COVER" but the air is actually taken from the cargo area were it seems there would be a lot more dust or if you are packed up, you would potentially block the intake.  There is no warning about blocking this vent, so making this mod would make even more sense.

I then pulled the cover off the back side and I found a 1.25 inch PVC fitting

It looks to me like it would be much easier to make the mod from the back side of the wall.  The connection there is simply a 1 1/4 inch PVC elbow there.  It could be immediately up-sized to 2 inch (to alleviate any flow restriction concerns) and continue up from there.

I'm also thinking that I could actually block the front vent and install a second snorkel to provide the air taken in from the front.  This way, it would still get air circulation around the motor, so when I stop, this heat will not come back into the passenger compartment.

Thanks a bunch for that post, it may have been a  long time until I opened this cover to look at it, and may have caused premature problems.  I think this will be my next mod.  I will try to post step by step as I do it.

[EZ Rider]

Hmmmm,  My photos didn't upload.  Will upload them somewhere else and provide a link.

[EZ Rider]

Ok, lets try this and see if it works:

https://imgur.com/a/hlzRd2K

[NMKawierider]

Interesting...no others I know of come from the factory with that cover inside the bed..nor use a PVC coupling to port-through. Besides, even the 800s use a 2.25" intake from the filter. The box intake must be >= that. Even 2" would be too small....and we've proven that with our 2" snorkels on the 750s in the Kawasaki forums.  Even though I use a 3" on my stacks, I came off the box inlet with 2.5" turbo aluminum piping and sweeping silicone 90s and 45s....and it fit perfectly to the box's port. I can't imagine how that one must run with a 1.25" intake...that poor engine. The factory did not do that....pretty sure.   

[EZ Rider]

I'm not sure what to say...  I know I bought the machine new from the local dealer with 8 miles on it.  We went on our first ride and put 100 miles on it in about a 7 hour period and had no problems.

I am going to pull the front cover off again and inspect it for evidence that someone has made modifications, and if I can prove it, the dealer is going to get an ear-full.  When I get this cover off again, I will take a picture from the front side and upload it.

That said, is there any one out there that has a 2017 ZForce 800 that can pull the inlet cover and take pictures of what it should look like so I can compare to mine?  I would be very thankful if someone could do that.

[NMKawierider]

Have to look kinda hard but you can see there is no exterior plate in the bed. I promise you they have made no changes from 2015 to 2018 on the intakes...Trail or EX. That was done at the dealer...and done wrong. I do have a how to on porting a 3" hole there and installing a screen, then a filter but I found that area gets about as much trash as it does under the plastics..just not the heat. That's why I finally move mine. Check these vids out:

[NMKawierider]

This is my slightly modified OE pipe. Yours should have looked very much like this one behind the grill.

[NMKawierider]

This was my first intake modification. All the tubes were like this but just ended inside that area with a prefilter bag over the end.

[EZ Rider]

That is almost exactly what mine looks like.  From looking at that picture, it still draws the air from the cargo area and not from the passenger compartment like the warning sticker says.  The difference on mine is the smaller coupling going to the rear.  Where your picture shows what appears to be a 2.5 inch inlet, mine is a 1.25 inch, and the cover that was installed forces the air pickup from the bottom of the cargo area.  Like you mentioned, a good area for dirt and other trash to collect.

https://i.imgur.com/dQEJ06T.jpg

I just watched your mod video... I like the time and thought you put into your mod.  I would question one point of it though.  Without taking measurements and doing the math I would tend to believe that the the cross section of the plastic piece that mounts between the cargo bay wall and the air filter box isn't much more than that of a 2 inch diameter round pipe.  Air shares pretty much the same properties as water moving through a tube where volume flow is lost in the length of the pipe and bends.  If it goes through a SHORT narrowing area, the velocity at that point is increased but once gets past that narrowing, it returns to almost normal.  The longer the pipe and the more turns (turbulence), the greater the flow loss.  Much like the way an engine header is designed for smooth flow and no Back Pressure.

I think for the moment and until I can complete the intake mod, I will simply remove the back cover and put a screen on it similar to the one you used.  Anything I can do to keep from accidentally blocking or restricting it.

Once again, thank you for your help and info.  This is a GREAT forum!

[NMKawierider]

You can always do what I did for testing- rig sensitive vacuum gauge to the water collection nipple on the airbox and have enough line to lay it on the passenger seat and take it out for runs. On mine, with nothing done to the stock setup, with it nailed at 5,000 RPM going down the road, it held right at 2.25 inches of vacuum. This was to be my baseline. Because it didn't have any until 3,000 proved there was no EPA requirement for noise incorporated so the goal should be no restriction. The first mod only dropped it to 1.75 inches. Opening it to 3" and using a mushroom filter dropped it to 1.25 inches but  taking the intake tube off completely held the gauge at zero..  so I knew the issue was in the pipe. The next mod was replace the tube with a full 2.5" all the way. That did it. No more airbox restriction even all the way to 7,000 RPM.  Not very scientific...but it was effective for my needs.  

This was the second mod to the 3" using the same tube:

This was my write-up on changing out that tube to the 2.5" before I move it to the outside:

http://cfmoto-forum.com/how-to's/z8-engine-air-intake-tube-change-out/

[cr2crf]

I'm not sure what to say...  I know I bought the machine new from the local dealer with 8 miles on it.  We went on our first ride and put 100 miles on it in about a 7 hour period and had no problems.

I bought mine from the same dealer and have the same plate.  They said it did reduce the dust and that CFMoto liked their design.  Not sure if I believe them on that.  I had seen NMK's air intake design prior to getting mine so I knew I was going to change it.  Wish they had left mine stock so i could drill my own holes.  But I asked them if I did further alterations to the air intake would it void the warranty and they said no it would not, as long as the mods were beyond the mod they did.