KDX Filter box modification

[aliikai]

I have read about several modifications to the filter box to improve airflow. 1. Remove snorkel, 2. remove snorkel and drill some holes in the airbox lid, and 3. remove the lid altogether. Has anyone out there done any/all of these modifications? Are there any problems with any of these options? I don't ride through rivers or anything like that.

 

[Michelle]

When I got my KDX, it had the snorkel removed. I decided to drill some holes, then figured I'd drilled them in the wrong place and have ended up nearly cutting off all the lid. The only intact part is the edge (so it can sit on the airbox) and enough room for the CDI (saves moving it).
No problems that I've discovered, except the whole air filter gets dirty instead of a tiny part of it - then again, I'm a wuss when it comes to water.

 

[wibby]

I took the whole lid off mine and mounted the regulator to the airbox itself, only problem I have is I have to clean my filter after every single ride and my bike is way louder than 'Carvr's bike!

Last time I asked, he still had the snorkel on his, I believe he told me it sounded too "Wonky" for him! ;)


Hopefully my dirty filter problems are over for a while, as it has been raining here for over a week! No more freakin' dust!!

While some people are talking about putting there bikes up for winter..... We are getting ready for our riding season! Fire Season has finally been lifted!. :)

 

[motrhedx81]

This past weekend I decided to check my bike out a little bit (just got it this summer). I used a 1/2" drill bit and drilled about 17 or so equally spaced holes on the part of the lid where the snorkel mounts. Most of the holes on the top where the snorkel enters and a few on the little face where the lid dips down facing the snorkel inlet. It ran a lot better and was just a little bit better. I didn't remove the lid or put too many holes in it cause I know I'll end up in some water somewhere and don't want to drown it.

 

[motrhedx81]

"It ran a lot better and was just a little bit better."

just a little bit "louder"

 

[gwhII]

I'm with the others. I pulled the snorkel and drilled two two-inch holes and the difference is noticable with just a bit more noise. Time for a UNI filter I think and I'm also thinking about getting pcracingusa.com's pro-seal.

Best,
Greg

 

[aliikai]

I just got done drilling 11 1/2 inch holes around where the snorkel used to be mounted. I took off the snorkel. What a difference, the best part is that this modification is free. Bike runs better, and has more power. Thanks for the feedback

 

[eldrm]

i've also done the drill and remove snorkel method and after quite a few deep water crossings have yet to drown out..........

 

[John Harris]

I just cut mine off behind the cdi box and received all the advantages noted above. I was concerned about transporting in rain and wind on trailers and trucks, but surprise, surprise I have never had a problem. I expect the seat hangs down enough to prevent most of water from getting in there and the air box does have a drain. Oiled foam is very water repellant. Easiest and cheapest mod ever!!!!

 

[cicone]

Got the whole lid off and the VR just dangling around. While you're in there you may consider this.
Copy of today's email to Gatorkdx: Took the left frame strut off last night and removed the entire airbox assembly. After complete teardown ---boot,box,filter frame,and retaining ring. Scrubbed in the driveway---filthy!! Put back together and sealed boot/box interface with blue rtv and installed newly cleaned and oiled filter---sweet. Looks like I need a new intake boot and am ordering complete bearing set swingarm/pivot assembly---that ought to be fun given everything I've seen on the kdx site. Does this matter?? I don't know--but it sure was fun!!

 

[Lizard Lips]

I cut about a 2 x 3 inch hole in the top of my airbox where the sorkle used to be. The bike runs great, but the noise was considerably worse. I'm putting a new lid back on with my snorkle to see if it makes a dif in the power. I also have a rev pipe and RB mod so I would rather have a quieter bike if it doesnt cost too much in loss of performance.

 

[bhiner]

Four key steps for air box mod success:
1) Remove snorkle and cdi
2) Wire tie cdi to frame
3) Remove lid
4) Fling it upward a 30 degree angle(outside)!!!
Free horse power and a frisbie to boot... Better than a Happy Meal!!!

I have ridden mine like this for over a year in all types of weather and terrain and had no prob's.

The fact that the whole filter is dirty is an indication that you are finally getting full use(breathing) of your filter instead of 1/4 of it's area.

 

[s.d.duner]

it seems odd that you feel a performance gain from just taking off the snorkel.

doesn't the hole that you remove it from have the same area as the snorkel's mouth. I think mine does.

also I thought that the snorkel may act as a "ram air" effect (to a very small degree)

from what everyone here says, I guess i'll remove it and see how it feels. Couldn't hurt anything, Right?

 

[Dawg_enD]

They aren't talking bout just the snorkel. They are talking about removing the entire airbox lid.

 

[slyder]

the best thing you can do is fling the air box lid.your kdx will thank you for that. i finally got rid of mine and every thing is better. more power and more volume to boot. together with the fmf desert pipe and power core 2 silencer the bike really screames. boyssen reeds also help. go ahead fling that lid!

 

[pketchum]

I'm with the others. I pulled the snorkel and drilled two two-inch holes and the difference is noticable with just a bit more noise. Time for a UNI filter I think and I'm also thinking about getting pcracingusa.com's pro-seal.

Best,
Greg

Did you ever buy the Pro-Seal filter? I'm thinking about purchasing one and would like to know your thoughts.

Thanks,

Phil

 

[gwhII]

Did you ever buy the Pro-Seal filter? I'm thinking about purchasing one and would like to know your thoughts.

Thanks,

Phil

Howdy Phil,

Yep, I bought the Pro-Seal filter and like it. I haven't seen any indication that it's not sealing. The seal is approximately .5 in wide and about 1-2mm thick. I'm using UNI filters and the lip on those is pretty substantial so everyting looks tight. I like not having to mess with the grease.

Best,
Greg

 

[jnugent]

I cut the snorkel off flush inside the box so air could be drawn by the whole filter and drilled 6 1 inch holes in the lid. I put Uni filtered air vents in the holes, they prefilter the air some what so the filter does not get as dirty. The noise did not increase much and there is still good protection from water. I also have the Pro seal and have been very happy with it.

 

[bcVulcan]

Howdy Phil,

Yep, I bought the Pro-Seal filter and like it. I haven't seen any indication that it's not sealing. The seal is approximately .5 in wide and about 1-2mm thick. I'm using UNI filters and the lip on those is pretty substantial so everyting looks tight. I like not having to mess with the grease.

Best,
Greg

2nd that!
The Uni fits so much tighter than the stock. That's GOTTA be better. :cool:

 

[1tontj]

Also for those of you that kept the air box lid full of holes like I did: take a womans nylon stocking and cut the foot off it. Now put the air box lid IN the stocking, and reinstall it. This will reduce the mud and crap that goes in the box without reducing flow.

Phil

 

[pketchum]

I cut the snorkel off flush inside the box so air could be drawn by the whole filter and drilled 6 1 inch holes in the lid. I put Uni filtered air vents in the holes, they prefilter the air some what so the filter does not get as dirty. The noise did not increase much and there is still good protection from water. I also have the Pro seal and have been very happy with it.

That's a very good idea (cutting the snorkel off flush inside the box) so that the whole filter is used instead of just a small section. How do you like the small Uni filtered air vents? Isn't that kind of a minor PITA to clean 1 big filter and 6 smaller ones? It's a good idea but I've always wondered how practical it is. Lord knows I already spend too much time in the garage.

Phil
'94 KDX 200

 

[jnugent]

I dont oil the foam in the inserts, so all I do is pull them out and use the air hose to blow the dust out.

 

[farmerj]

I didn't like the "honk" (louder noise under acceleration) that I got by removing the whole lid. I did it like bRush - and am happy! (his pic below)

lid pic