Surface CVT Filter Idea
I was trying to come up with an idea that would increase my range between cleaning the little filter I put under the CVT intake grill until I had time to re-visit my filter box system and thought about something like a dust mask domed over the intake grill. I looked to several types of domed airfilters and because of price I chose Maxima and this style:
I needed one that was at least 7” x5” x2” as that was the amount of room behind the seat and would cover the grill. But because all I could find on specs was packaging size, the one I ordered wouldn’t work. Bummer..then I saw my old fire suppression screen out of my Brute’s airbox and the light bulb went off.
It fit over the grill so I cut two pieces of 1/8” expanded metal several inches larger and clamped them together with vise grips. I then started working the two into a dome that would be at least an inch high and configured like the fire suppressor. Once doned I form a flange around the edge like the model. Then cut the inside piece way down to give support only. Using the top piece as a pattern I marked and cut a extra piece of UniFilter material to fit the metal with a little extra. Then adjusted the outer metal to fit the plastic contours. Then using the inner as a template, marked and cut the second layer of material out leaving the edge as a sealing surface and a single layer of filter material for the intake:
Located where a mounting bolt should be on the grill, formed a ¼” bolt to fit around a fin and secured it with a little pinch force:
Then I needed a sleeve to help guide the stud through and provide a stop for the wing nut so it would maintain the dome and not over crush the metal:
Then slapped that puppy on there:
The wing and stud are no where close to the seat:
Not real pretty but seems very functional.
If you can get a dome filter that has an interior size of at least 5”x6.5” and can end up 2”s or less tall, you can avoid most of this fab work. I think you can use up to an 8x8x3 and make it work. You will still need a stud and a sleeve…but that’s it. No need to oil this filter. Just when needed pop it off, give it a slap or two…or a wash with water and reinstall.
UPDATE: 8/23/16:After two ore failed attempts to find a store-bought filter that would work to replace the home made one I decided to just use it and make a nicer bracket. From some 3/4" stock I made a frame that plugged-in on one side like the door did and used the screws on the other side to retain it. Gave it an overall 3/4" arch above the center surface, installed a 1/4 20x 1/2" bolt, filled in where the door latch was with some black RTV. Here's the frame before filling in the latch hole:
And one with the filter in place:
Now, because I run this filter dry, when needed I just pop it off, give it a few slaps if on the trail or rinse with water if home and slap it back on...and go!
Special side note: That door latch hole - is NOT sealed with the door in place. Right behind it is the LR tire and we all know how much stuff gets tossed up in that area. Before my ride on the 21st that intake boot was clean and I had the door in place. All that dirt you see in the above photo didn't come through the filter, it came through that open hole. That may be where a lot of this trash is coming from we are finding in the CVTs.