Airbox Support Ring Mod.

[USAF400EX]

If anyone is using a K&N Filter like myself you will appreciate this. After riding last week I took off my filter cover only to find my filter sitting on the botton of the box. After putting it back on I noticed that even with it tight, little effort was needed to pull it off. I looked around for a support ring but couldnt find one so heres what I did. Take your old foam filter cage (metal part that goes inside) and using a dremel or hacksaw, cut off the lip that would normally slide into the intake boot. clean it up a little and squeeze it into the hole and presto-a no cost intake boot support ring. This mod worked very well for me. You can really torque that clamp down now. Anyways let me know if anyone else has tried this. And one more thing.. Anyone looking for a K&N filter should check their website for the universal filters..Just take the measurements and check it out I used part # RU-3550. It was about 15 dollars cheaper than the one made for a 400EX.

[Lorduss]

Very good info. i havent gone to a aftermarket filter yet, but personaly im a nut for making sure my airfilters secure. ill do that first thing, not running with a filter well be making you get a new piston and sleeve in no time.

[Deathbringer]

Did you use the one they gave or the original one....???? I have had mine on for a year now and it has never come loose?? I'm just wondering if maybe your clamp isn't seating right, make sure the underneath is holding or siting right. But that is a GREAT idea, I may just do that for extra protection agains't it falling off.

[Dave400ex]

Doesn`t Hinson make Airbox support Rings?

[USAF400EX]

Im sure Hinson does make support rings for your airbox but just like any other Hinson product it probably costs a fortune. Using this mod is FREE$$$ Oh and not sure what you meant by using the "original one" But I used the original cage that came with the stock filter. K&N doesnt use them. The thing that I noticed is that using a socket to tighten down the filter you can just crank on it forever while the intake boot is getting all distorted and there is not really a way to tell taht it is doing it. My advice is to tighten down your K&N just as you normally would and then grab the end of it and see how hard it is to pull off. If it comes of with a little effort it might be worth your while to do this mod or get a support ring if you have money burnin a hole in your pocket. Either way would be cheaper than a new piston and/or sleeve. The hole process took about an hour, but knowing that I couldnt pull my filter off anymore assures me that it wont come off on the trail. If anyone uses this mod let me know how it worked out for you.

[Dave400ex]

I found the Hinson Rings. They are like $7.00. Not bad. They are only for a 250r though. Will they Work on the 400EX?

[James70214]

Warriorman
Where did you find them for 7 I need to get them an Nacs has em for 19.99
Thanks
James

[Dave400ex]

Really? I thought Nac`s had them for $7. Maybe I was thinking of something else. Well $20 isn`t Bad. Will they Work on a 400EX though?

[James70214]

THey are 19.99 for 2 of them at Nacs. Darn I thought you found a cheaper place. O well. I don't know if they fit a 400.

[Dave400ex]

No if you get them let me know if you think they would fit on a 400EX. I might have to Call Nac`s and ask.

[Live2Ride300]

USAF400EX-

That same thing happened to my friends 400EX, he has a K+N filter on his, and while we were eating lunch during a day ride, we checked out air filters and he found his sitting in the bottom of his air box so he put it back on and every 30 min he would check adn make sure its still on there good. I'll be sure to tell him about this mod, thats a good idea man, thanx alot, thanx for the part number for the universal K+N thats alot better than buying the one for the 400EX. Thanx again man, later

Charlie

[Dave400ex]

Man I might have to try this Idea. I don`t want my Filter to come off. Do you have any Pictures?

[Live2Ride300]

Anyone know what K+N's website is?

[USAF400EX]

Its knfilters.com

[USAF400EX]

heres the before pic if I can figure this thing out

[USAF400EX]

after the cut

[USAF400EX]

another

[USAF400EX]

and installed. I had to tap it with a hammer to get it in. I intstalled it so the "cut" side would face in toward the carb. Installing it this way will put the lip of the ring towards the airbox which the filter will slide over and it also gives a nice groove for the clamp.

[Dave400ex]

Thanks for the Pictures now I know what you are talking about. I might have to do that.

[Live2Ride300]

Looks good man!:)

[USAF400EX]

bump

[RED121572]

K&N is somewhat known for making air filters that do not fit properly. (cars and ATVs) The first K&N I bought for my Ram Cummins didnt fit properly and I sent it back. They sent me a new one. A buddy of mine is having problems with his filter in his 400 as well.

[whiteknuckle]

im gonna do that even though ive had no problem thanks alot!! but whats that mess around the hole in youre airbox?? it looks like youre quad is a hundred years old?????

[USAF400EX]

When I took apart my airbox to drill holes for the vents, I re-siliconed the ring around the intake. It just started coming off a little bit, thats all. It is not a 100 years old, although sometimes when Im done riding it looks that way. Youre not supposed to be looking at that though, the pic was for the SUPPORT RING!! Lol

[Dave400ex]

I have never had a Problem with my K&N Filters. They always work Great. I think I need to do this Mod though just in Case.

[whiteknuckle]

LMAO!! oops sorry just kinda noticed it there! thanks for the mod though im sure were all happy you put it on here!