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Waterproofing your Intake??

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i was looking at the housing for my airbox and the intake. it looks like their are so many places water can get in. i see enduro guys hit water up to the seat. i dont understand how they dont just hydrolock thier motors. i got water in my airbox by washing it with a hose. are their methods i can take to waterproof it? has anyone ever thought of blocking off the intake (which is on the bottom behind the mud flap) and maybe snorkeling it with a tube up to the seat. just wondering

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so every off road rider just hits water crossins with the stock air housing as it is and allows water to spill in and get sucked into the motor?

i see

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you can't completely water tight an air box, becuase it would be air tight. And yes, we charge water crossings with stock air boxes. If you hit it fast enough, water wont have time to get in

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When your front wheel is in the air when you hit water, your air box is also farther away from the water.....

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What happens is that the bike pushes the water out of the way and the water can't get into the airbox. If you come to a stop, then the water can get to your airbox. I've gone through water that was almost up to the seat before w/o getting enough in the airbox to affect the engine, and that was on my 96 RM250 and not just my KTM300EXC which is built for off-road use from the get-go.

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how is the ktm300 different in this respect? just curious because im looking at these bikes.

die_trying, i know u cant water tight it. i was thinking of siliconing where the plastics and number plates meet (since they simply overlap and do not seal) and then block off where the air comes in stock (down bellow on my bike) and route it so the air comes from the top more. just a thought. because what if for somereason ur stopped in the water or forced to slow down. water chugs into the airfilter

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I'm not really sure if the KTM airbox is set up differently from an MX bike, I just wanted to point out that the RM didn't have problems either in case the KTM is different from a typical Japanese MX bike. As long as you don't stop, you really should't have to worry too much. You can go pretty slow and still create the wake that will keep the water out.

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X2468, You can close some of the area's that easly let water in. Seal all the seems on the airbox where it is made from several parts. Be sure you don't seal the botom drain as it is critical if you do take on water. Look at some of the vent area's in the side panels and close those with duct tape on an as neede basis when you know you will encounter water on a rainy day of if you will have a creek or river crossing. When we race the OMA series, Bill Gussie, the promoter always runs them through some deep stuff, so we have to seal things up, but also balance that with allowing enough opening to let the bike breath. Let common sense and experience be your guide.

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X2468, You can close some of the area's that easly let water in. Seal all the seems on the airbox where it is made from several parts. Be sure you don't seal the botom drain as it is critical if you do take on water. Look at some of the vent area's in the side panels and close those with duct tape on an as neede basis when you know you will encounter water on a rainy day of if you will have a creek or river crossing. When we race the OMA series, Bill Gussie, the promoter always runs them through some deep stuff, so we have to seal things up, but also balance that with allowing enough opening to let the bike breath. Let common sense and experience be your guide.

thanks for the info DROB. one question, what product or amterial do you use to seal the airbox where it is made of several parts? silicone glue?

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i came to thinking. you think it would be possible to make a filter made with gore-tex like properties? as in, its filtering is larger enough for air yet too small for h2o to fit through. i wonder if its possible or if it would work. or myabe their are gore-tex style pre-filter wraps??

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so every off road rider just hits water crossins with the stock air housing as it is and allows water to spill in and get sucked into the motor?

i see

We dont have water here in Vegas. The casinos took it all for their fountains.

John in Vegas

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Good quallity silicone works well. Watch it over time because it can be attacked by gasoline and solvents. Twin air makes a product called a GP cover that we use over the filter when we are trying to keep the water out. It is made of fine nylon and lets air through and keeps the water out. You have to walk a fine line with the gp cover on 3+ hour races if the rest of the coarse is dusty, you can clog the cover and starve the bike for air. In the shorter races or trail ride situations, the GP cover would work great. In dusty conditions we use the Twin Air dust cover. Many off-road guys like Mike Lafferty have been using them for years. It is a course foam cover that is about 1/4" thick that goes over the filter dry. It stops most of the dust and when you hit a bump it falls into the bottom of the airbox. This works very well as it doesn't clog up like the fine material of a filter skin. Check out these products at Twinairusa.com. I am sure you can order them through the TT store. You will be amazed how clean your filter stays with a dust cover on it!!

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thanks for all the help DROB. not sure if your chirs or chris's dad or someone else, but thanks.

im wondering now why dont they dont put ATV style airbox's in dirtbikes. ATV airboxes are totally sealed and waterproof except for teh designated intake which is usually routed in and inteligent way as to avoid water from coming in easily.

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I am Chris's dad. My name is Dennis and everyone calls me DRob. Anything but late for dinner will work. Most of us off-road guys have to make things work because the motorcycles were not intended to be used in as severe of conditions as we someimes find ourselves. That and those quads already weight hundreds of pounds, so 10 more won't hurt. I like that part of the challenge, a little creativity and common sense goes a long way.

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good point. i guess i got spoiled and lazy. before this i rode a 4x4 quad which i knew could crawl through waste high water like a tank. but like you said, the challenge of the bike is much more fun and rewarding.

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I know that on my intake, the main area that air goes in is way up at the top of the airbox... just under the seat... and i've been in water that deep (recently actually) and i had the stock snorkle in (which i have recently removed... better proformance, but will put back in if i expect nasty water crossings) but way i figure it, as long as the top of the box is about leval with the water i should be alirght... also, if you are in that deep, keep on the gas the best you can and use your feet and legs to try and channel it away from the airbox.... don't stop untill your either though or you hear some gurgalling... with the latter.... hit the kill switch, that's water headed into the airbox fast, and we all know where it is gonna end up next.

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what about taking some plexiglass, and making a fence like shape around the bottom of the filter, following that shape of the filter, going up high enough to prevent water least 4 inches into the airbox.

that would be more than would ever be in there in most cases.

its essentially making a half airbox inside the aribox. lol

i doubt if done right and wide enough form the filter, it would make any difference at all in breathability.

just a random thought

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I know that on my intake, the main area that air goes in is way up at the top of the airbox... just under the seat... and i've been in water that deep (recently actually) and i had the stock snorkle in (which i have recently removed... better proformance, but will put back in if i expect nasty water crossings) but way i figure it, as long as the top of the box is about leval with the water i should be alirght... also, if you are in that deep, keep on the gas the best you can and use your feet and legs to try and channel it away from the airbox.... don't stop untill your either though or you hear some gurgalling... with the latter.... hit the kill switch, that's water headed into the airbox fast, and we all know where it is gonna end up next.

i dont know what kind of bike u have but that system is much better than the one shared by my Kx and my step brothers yz125. our intakes are at the very bottom just behind the mud flap and point to the ground.

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