internal pressure?

Steve Northrop blackgpz at
Sat Mar 17 15:53:42 PDT 2007

The KLEEN air system is a passive air injection system.  Air is drawn from 
the airbox, through the reed valves in the valve cover, through four 
passages in the cylinder head. This passage is the small circular opening 
right next to the spark plug with the hollow roll pin in it you can see when 
you have the valve cover off. Each passage leads to an opening in the 
exhaust port. The venturi effect of the exhaust gasses passing this opening 
is what draws the air in. This is why it is important to make sure the 
"figure 8" gaskets are in good shape. Whether the KLEEN air system is intact 
or if the reed valves have been blocked off, a low pressure area exists such 
that if it is not sealed well beneath the valve cover, oil can be sucked 
into the exhaust. I tapped the passages and epoxied in some 1/8 pipe plugs. 
The PCV system is the hose that comes out of the rectangular cover at the 
back of the engine above the transmission. Remember the crankcase is open to 
the transmission so it vents both.

Steve in Western NY
'96 GPZ1100
'02 Daytona 955i
"You Can't Fix Stupid", Ron White

----- Original Message ----- 
From: "schnowz" <schnowz at>
To: <gpzlist at>
Sent: Saturday, March 17, 2007 7:15 PM
Subject: Re: internal pressure?

> Steve,
> I'm not understanding this,where is it connected to the exhaust port?
> The diagram shows it connected to the airbox, inlet manifold, and rocker 
> cover.
> I thought it was acting similar to a PCV valve???
>  Pete S
>> From: "Steve Northrop" <blackgpz at>
>> Subject: Re: internal pressure?
>> To: "GPZ LIST" <gpzlist at>
>> Message-ID: <000c01c7680b$a0467710$6900a8c0 at DB3HB511>
>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>> reply-type=original
>> Dave,
>>     The absence or presence of the KLEEN Air system has no bearing
>> whatsoever on jetting. This passive system introduces air at the exhaust
>> port, it does not add any additional air to the engine. Blocking off the
>> reed valves is no problem because they have nothing to do with venting
>> internal pressure to begin with. This vent is at the rear of the engine
>> above the transmission with a hose that goes to the airbox if you are 
>> still
>> using one. The reed valves in the KLEEN Air system act as one-way valves 
>> so
>> when exhaust gasses pass by the opening in the exhaust port, it will draw
>> some air with it. The reed valves keep exhaust reversion pulses from 
>> pushing
>> exhaust gas back through the system. Sorry, but putting it back on was a 
>> lot
>> of work for nothing.
>> Steve in Western NY 

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