Kawasaki Sportsbike Riders Club - Australia - Online Forum

i got all enthusiastic on a double points weekend and pulled the tank off the Z...
did the plug gaps and cleaned the air filter.
while i was there had a squiz at the kleen air thingy..

i was going to give it the yank and get get rid of it, but dad seemed to think that the pipe coming from the airbox and into the rocker cover is actually the pcv valve, and removing will cause it to blow seals and stuff.
anyone got any experience...

btw the plugs went well, reckon i'll get another 10kw at the wheel now on the bum dyno that is, (just coz i did it myself)

your old man would be right about that. rocker cover/crankcase -> airbox = pollution-control stuff. Seal blowing indeed.


That reminds me of a joke: A penguin was driving his car along on a summers day. He pulled into a servicestation as he was having car problems (it was a volvo you know...) and the mechanic said "hey i think you've blown a seal", The penguin started looking all embarrassed and wiped his beak and said "nah it's just icecream".

back on-topic, i'm not sure where the kleen-air thingo would live.

ZX12R's have them too.
Advice on ZX12R.org was to remove, but run into Crankcase breather.
I have a modded bike (pipe, BMC's & PCIII) and it when I did it, it made it FEEL like it ran smoother (no backfires either) but without a Dyno who knows if it robs power or not ?
I have not blown seals or the like BUT who knows ???
Mine was running like a pig down low and I had nothing to lose (you can put it back pretty easy) but if your bike is running fine, leave it alone....
I would not change it for NO reason.

mike-s wrote:...i'm not sure where the kleen-air thingo would live.

Funnily enough they live in the rocker cover. There are two reed valves underneath rectagonal covers that have a bit of tubing each, which joins together in a big plastic doohicky that then has a bit of tube running to the airbox. Totally seperate from your crankcase breather tube.

*scratches head*
I thought that the kleen air thing & the breather were two seperate things.
i.e. the rankcase breather vented to the airbox so that oil fumes & the grotty bits of oil went into the airbox so they'd be burned by the motor.

I thought the kleen-air thing was a sort of one way reed valve on the exhaust that would ONLY allow air to go into the exhaust pipe when there was low backpressure (downshifting, compression braking, etc..), to allow extra fuel in the exhaust to be burned off before it came out the can.

Sorry not specific enough.
You remove the hose from the centre of the T piece and go to the crankcase breather. All the Kleen Air crap was on this hose.
There are plugs to be fitted and I dont imagine they will be the same place as on my 12 (into the airbox).

I only mention MY findings as Micron told me that they have the same problems with the Z1000 they do with the ZX12R (rough running down low, ie below 2500rpm) and so MAYBE it is relevant to you, if not ignore it.

IF it is to stop the backfiring make DAMN sure you check that the exhaust is not just leaking first....
IF you REALLY want to know I can send the post tomorrow or you can go to the Canadian ZX12R.org website and search for Kleen Air Removal.
They have good pictures BUT may not be relevant to your thou'.

Like I say if the bike is running OK leave it, because -
I only did what the website said (BUT my bike had a electric vaccum pump!!) and it did make it FEEL like it runs smoother.

BUT other than that I know shit, I just know it worked FOR ME.

Ummm, I think we have some crossed wires here.
The crankcase breather comes from the rear lower portion of the engine, usually into the airbox.. This should stay.
The KLEEN air injection is on the top of the cylinder head rocker cover and sucks air from the air box into the exhaust reed block. This can be removed, if you want.
KLEEN stands for Kawasaki Low Exhaust Emmision so you can guess what its purpose in life is...

"Use of KLEEN (Kawasaki Low Exhaust Emission) catalyser system helps keep exhaust emissions environmentally friendly. Honeycomb catalyser located in the muffler helps ensure that the 10R meet Euro II emissions regulations."

I've never heard it causing any problems, It was removed on my zx9r race bike and it certainly cuts down the backfiring on the 10...
A lot of performance shops sell the block off plates, like Muzzy, Ivans etc, but you don't need em..

Save the environment and leave it on..

whens that spanner day Dave?? winter is near... garage days are lookin better option...

Wattie I can email you detailed pics and description of what to do on a ZRX if that helps.

mailto:hofman20@optusnet.com.au

This is the start of the blurb on ZX12R Kleen Air removal off ZX12R.org
Didnt include the lot as you are better going bike specific (see above).
Just thought this said it al lot better than what I have been trying to explain with my very limited knowledge.

"Kleen Air Removal With Crankcase Vacuum Procedure

Here are the steps documented to perform the removal of the Kleen Air system AND add the crankcase vacuum modification.

This is an alternative to the Muzzy Block Off procedure I documented on this site. The choice is yours. The pros of this procedure are:

1) It costs about $5 to do
2) The reed valve covers do NOT have to be removed. This is a major issue, because the two inner reed cover mounting bolts are almost impossible to get at with a socket due to how tight the clearance is. If you try to remove them without the radiator out, you will learn the hard way what I mean.
3) This procedure can be done without removing the radiator OR valve cover heat shield.
4) Claims of .5 to 5.0 h.p. have been made on this mod. I cannot dispute or prove those numbers, but I can tell you that a large number of race teams are running this mod. After a year of reading and studying and talking to knowledgeable people on this mod, my gut instinct is that it is probably good for 1-2 h.p on the 12. But that is free horsepower, no matter how much, and you get rid of the backfiring by removing the Kleen Air at the same time.

Essentially, this modification removes the Kleen Air vacuum pump and routes the crankcase vent tube (which exits above the counter-shaft sprocket cover) to a tee installed between the Kleen Air reed valves."

I dont know about the HP but it made my bike run "cleaner" and as I dont have a cat then it is moot whether it polutes less or more (and is nothing on my smokey V8 anyway.....)

Had em on my ZZR. Pulled the valve cover and liquid steeled the holes in the cover then removed the reed valves on top- did it to both my ZZR11 and 12- runs smoother. Maybe some small power increase.

http://www.riderforums.com/attachment.p ... 1361&stc=1

this is what i have, can i just block the long pipe off at the airbox??

I cant view it, I am not a member there, should I be?

As long as you plug the airbox, and plug the rocker cover(or pipe coming from), so there is zero leakage, you should be cool.

join if you like, a few xrx's on there.
1000s of Zs i use it for reference
i think i'll plug the big pipe...

Ummmm I'm putting mine back on

It has just started running like a pig until it gets warm and then runs hot....
Dont know if it is the Kleen Air but it is the only thing I have done since it last ran good.....

At least it is easy to put back.
Doesnt mean it doesnt work for you but and it CAN be felt.