DIY- Removing the Kleen Air System Hoses and Plugging the Holes on a 08 250R

[kkim]

Kleen air system... what is it? It's a basic air injection system that draws air into the exhaust system to lean out the exhaust gases at certain throttle settings. It, in conjunction wit the 2 catalytic converters in the stock exhaust system, lowers emissions to acceptable EPA levels so Kawasaki can sell the bikes in the US.

Who should remove this system? With the stock exhaust in place, I have read that it may be a good idea to leave this system alone because if you did not lean out the exhaust with the cats in place you could cause converter clogging problems. No real proof if this is true or not... do so at your own risk if you decide to remove it.

If, however, you have installed an aftermarket full system on your bike and have no catalytic converters to deal with, you may want to consider this mod. I have installed an Area P quiet core system and ever since I have installed it, I was getting popping and backfiring at very small throttle openings around town and on downhill decel throttle settings. When I plugged the hose that ran from the airbox to the cylinder head, which is what the Kleen system uses to inject air into the exhaust, the popping and backfiring disappeared. It made a difference for me, so I decided to pull all the plumbing from airbox to cylinder head and plug the holes left by the hose and associated equipment.

This DIY shows how to remove the hoses and plug the holes left by it's removal.

Hose I removed is the 3/4" looking hose directly beneath the backbone of the bike with the gold colored keeper.

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Remove the keeper and pry off the hose.

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The hose is being pried off a vacuum controlled valve that needs to be removed. Simply slip it's rubber isolators off the bracket it sits on. From the valve, there is a short length of 3/4" hose that runs to the top of the cylinder head. Remove the hose from the cylinder head.

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Remove the the valve and 3/4" hoses from the bike. There will be a vacuum hose that ran to the valve. Follow it back to a T and remove the hose from the T and cap the spigot on the T. I bought some 3/16" vacuum hose plugs that fit the T.

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To make some plugs, I used 1/2"ID fuel hose, some old oil drain plugs I had laying around and some tie wraps.

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You need to plug the hole at the top of the cylinder head and the hole at the airbox where the 3/4" hose came from.

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And that’s it. The result is a lot less clutter under the tank area and hopefully no more backfiring and popping.

If I missed anything, I'm sure I'm going to be hearing about it.

Some pictures of the plumbing that was removed.

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More extra pics:

[HKr1]

Originally Posted by kkim

Who should remove this system? With the stock exhaust in place, I have read that it may be a good idea to leave this system alone because if you did not lean out the exhaust with the cats in place you could cause converter clogging problems. No real proof if this is true or not... do so at your own risk if you decide to remove it.

I know for a fact that an over rich condition will melt those honey comb cats and casue flow problems. It's really funny what Kawi is calling a cat on the 250r. That same piece in the muffler, is in the header. So from the Y-pipe juntion, to where it bends to go up to the muffler. Theres one of those so called cats. If you have the muffler off, look down in there with a flash lite. You will just see the end of it. I ran a bore scope thru there, it's open thru that piece to the y-pipe(just as it was in the muff).
I think next time we have the bike apart, we will plug off this AIS system also.

Heres a pic of that piece that came from the muffler. I dont see any real way to remove it from the header, but to cut at the y-pipe.... remove and weld back up. Dont think it would be worth the effort.

So anyway, plugging off this kleen air system (AIS) should be a good mod for those with slip-ons.

[ASecretNinja]

Yours looks way different than my pre-gen. How would I go about doing it on my bike?

And yes I did search, that is how I ended up here after wadding through 3 pages of nothing useful.

[Nevrfastenuf]

Originally Posted by ASecretNinja

Yours looks way different than my pre-gen. How would I go about doing it on my bike?

And yes I did search, that is how I ended up here after wadding through 3 pages of nothing useful.

I don't have a service manual for the pre-gen, but from the looks of the parts diagrams on bikebandit.com there is no kleen air system on the pre-gens...

I don't have a pre-gen so I could be wrong.

http://www.bikebandit.com/houseofmot...s-1995/o/m4025

[ASecretNinja]

Originally Posted by Nevrfastenuf

I don't have a service manual for the pre-gen, but from the looks of the parts diagrams on bikebandit.com there is no kleen air system on the pre-gens...

I don't have a pre-gen so I could be wrong.

http://www.bikebandit.com/houseofmot...s-1995/o/m4025

Wow nice link. The thing I want to remove is the fuel evaporative system (schematic shown in that link). Part # 16165 is loose and flops around. No way to re-secure it and its driving me crazy.

[Nevrfastenuf]

Originally Posted by ASecretNinja

Wow nice link. The thing I want to remove is the fuel evaporative system (schematic shown in that link). Part # 16165 is loose and flops around. No way to re-secure it and its driving me crazy.

I would maybe consider just buying a new strap pn/92072 on those diagrams and keeping the system intact.

If you are interested in removing it, I would read through the following two pages. From what I can tell the red and blue color coding is similar between pre-gen and new-gen bikes.

http://www.ninjette.org/forums/showt...ight=emissions
http://faq.ninja250.org/wiki/Hose_ro...ine_fuel_tanks

[wayanlam]

hi Kelly,

need your advice/help.

i went through your DYI one last time after having removed the kleen air from my bike, and noticed a little difference between our bikes:

in your picture you have like a 4 way splitter i think?



did you plug the one end that went to the kleen air valve with the blue bit?

where do the other two tubes go?

on my bike when we took it apart, i had a 3 way splitter, one from the fuel tank, one to the kleen air valve, and one to the carb.

since we took out the end from the kleen air, we were left with just the fuel tank and carb, so we connected that direct:



i haven't had any problems with the bike since i did this mod, so i think its ok, but id still like to know if that's what i was supposed to do, to avoid any problems down the road because i was too lazy to ask

thanks bro~
W.

[kkim]

on my 4 way splitter, one goes to the carb, which is the vacuum source, one is capped, one goes up to the fuel petcock (I think) and the last one is a separate hose I added which runs out to the side panel so I can check the carb sync easily.

you should at least have a hose that goes to the back of the fuel petcock off a 3 way splitter. do you?

[wayanlam]

yeah, well i have the hose going directly from the vacuum source (the carb) to the fuel tank (petcock) its the smaller hose plug, next to the fuel outlet. i wasn't, and still am not quite sure what it does, nor what the vacuum source does, lol

i removed the 3 way splitter since i didn't have anything to plug the 3rd tip with, and just went direct.

how can u check your carb sync, and whats the use to do so? i think i remember browsing through a thread that looked into that, but was a while back, and i read it before i even had the 250, so i didn't really pay attention to it.

thanks!

[kkim]

syncing insures the carbs are pulling equally by adjusting a mechanical device/linkage which controls the carb butterflies. I suggest you reread that post on syncing for a better explanation and understanding on how to do it.

A properly synced bike will run/idle smoother and pull harder from the low to midrange.

[Manimal]

Hi All,

I have a 2009 CA model.

First, thanks for the insight of correcting the popping / back-firing symptoms.

My plumbing is close to as pictured.


However, my CA model / version has a "T" that splits the hose (long hose pictured above) between the Vacuum Switch (Item 7, p3-6 of owners manual) and the Air Box. The split line / hose connects to the Canaster (Item 2, p3-8 of the owners manual), located on the left side of the motorcycle.

Therefore, I capped / plugged off the "T" end that goes to the Vacuum Switch. The other two hoses I left connected (to Canaster & Air Box).

I did follow the other steps of capping / plugging off the Valve Cover (or cylinder head cover) spout and the small 1/8" dia vacuum hose.

Question for the experts, why cap / plug off the valve cover (cylinder head cover) spout?
Does it blow or suck air (to/from the Vacuum Switch)?

[Dmitriy]

You can also grab on of these plate's here to make for a cleaner look:
http://www.shop.kyleusa.com/product....categoryId=121

[Perbeils]

This mod afect performance or just remove the popping and backfiring decelerating?

[wayanlam]

Originally Posted by Perbeils

This mod afect performance or just remove the popping and backfiring decelerating?

definitely removes the backfiring/popping sounds, which in turn lets you drive the bike a lot harder (by not feeling like a fool backfiring throughout the whole ride, lol) so yeah, in that case i would consider this a performance mod

[Thrak]

Do you guys think there is any negative effect to the extra pressure in the top of the case from this being plugged up?

[Momaru]

Well, FWIW it's negative pressure (suction) at the top of the cylinder head cover where short big hose of the the Kleen Air attaches. I've plugged it with my hand before, testing the sound of sealed vs unsealed. It's not a whole lot of pressure. Given the thickness of the metal used (even if our engine is mostly aluminum), I'm not concerned in the least.

[Thrak]

Originally Posted by Momaru

Well, FWIW it's negative pressure (suction) at the top of the cylinder head cover where short big hose of the the Kleen Air attaches. I've plugged it with my hand before, testing the sound of sealed vs unsealed. It's not a whole lot of pressure. Given the thickness of the metal used (even if our engine is mostly aluminum), I'm not concerned in the least.

Its not a suction at idle, its blowing out a pretty good amount of air...

I'm more concerned about the gaskets, not the metal of the engine.

[Ninja North]

Anyone had experience on doing this Mod' on an FI bike?

[Kitdog]

The only thing I could add to this is that when I did mine, I went to the local auto parts store to get the "vacuum plug" for the T joint and right next to where they are located I found random elbow junctions, so rather than buying a cap I got the elbow and replaced the T junction. here is a pic of what I exchanged, on the right is the original, on the left is the replacement. It makes for a cleaner install.

[Ninja North]

Thanks KKim - based on you DIY I managed to remove the Kleen-Air system from my FI bike. The back-fire was greatly reduced - I haven't had any since! There were a few different things from your carburetted bikes so I guessed a bit - after taking the tank off /re-installing it 4 times to check/correct my mistakes - everything is done! The bike is running great. Thanks again.

[Guinss]

For removal on FI 250R.

There is no 3rd hose, only the 2 large ones are there. There is an electric switch which operaters the valve here, instead of vacuum. Thats why there is no 3rd hose, but the switch, needs to stay on the bike for the FI-light not to light up. I wrapped the 2 ends in some electro-tape and placed it back on the bike. No air going through it, so the valve isnt doing much, but it keeps the warning light off.

[kkim]

Thank you, Simen, for your contribution. Good stuff!

[Ninja North]

Just to add to Guinss's post - our FI bikes here in Thailand has another hose which goes to a "cannister" - same as So Cal bikes.

[randomwalk101]

Sling Shot Racing has this nice cap for the 250.

[s2kenny]

Hey I was doing this to my CA model 250r.. and I have a question about some extra hoses.

Do I take these hoses off too and plug off that port? (the bundle that I'm holding)

[kkim]

if it's no longer connected to anything, yes.

[s2kenny]

Oh ok great, so I guess for the CA models you need to plug up 3 holes? 1 on the air box, 1 on the carb, 1 on the crankcase

[kkim]

Crankcase? Sorry, not familiar w/ CA stuff, but a pic of the crank vent would help.

[s2kenny]

Crank vent, I'm sorry. The silver square on top! With the silver tube coming up like a chimney

[kkim]

Originally Posted by s2kenny

Crank vent, I'm sorry. The silver square on top! With the silver tube coming up like a chimney

picture please. there is a crankcase vent that you do not want to block. I want to make sure exactly what we're talking about.

[s2kenny]

*gets off lazy butt*

Here is the hole on the top of the engine

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Here is the hole on the carburetor (brass fitting)

pic2.jpg

Thanks for all your help

[kkim]

Well, you do need to cap/plug the airbox hole and "chimney" at the top of the cylinder head.

That brass fitting on the carb is a vacuum source. What was connected to it before? I seem to remember more than one thing was connected to each of the vacuum ports on the carbs. (brass fittings)

[s2kenny]

Oops. It was connected with a T, and I don't quite remember where they hooked to to before. I'm going to have to try to pull up the diagrams for this

[drumm3r9]

kenny I'm in the same boat.....got everything plugged but not sure what to do with the brass fitting on the carb....hhmmm....

[s2kenny]

With some help from another member here, I learned that it's goes from the carb, to the bottom of the gas tank. It goes into the petcock. I just blocked off one side of the T and then put it back into the tank.

[drumm3r9]

aaahhhh i see....thanks for the help!!!!

[illrational]

DIY on removing kleen system made it a chinch...not sure if i like result but ill give it a ride or two plus with me about to shim and desnorkle i may be surprised.

[kkim]

Originally Posted by illrational

DIY on removing kleen system made it a chinch...not sure if i like result but ill give it a ride or two plus with me about to shim and desnorkle i may be surprised.

was your bike backfiring/popping after you put the exhaust on it?

[illrational]

All the time especially when i first started up...it kind of seems like its starving for air now...i didnt run it for long but i'll crank it up when i get homme and get back to you.


Sorry i put in wrong section Alex,dont mean to make you work!!
Side note: I should get that green and white smiley face on my bike...

[kkim]

Originally Posted by illrational

All the time especially when i first started up...it kind of seems like its starving for air now...i didnt run it for long but i'll crank it up when i get homme and get back to you.

starving for air means you think the bike is running richer, not leaner. I think with the mods you've done and not doing anything to the jetting (I don't see anything mentioned in your sig) has you ruining lean, not richer. watch out you don't do damage to your engine if you haven't adjusted your jetting to compensate.

I don't think you'll want the smiley face if that should happen.