FZRSupport: the FZROnline Archive

So the PO ditched the airbox for a twin KN set up. Its a California model with the air injection set up. But he put a bolt in the hose that attached the air injection valve to the air cleaner. Should he have done that? Shouldnt it be sucking/swallowing air ) ?

if its the hose i think you are talking about.... that is the crankcase breather... that should be open and ideally it should have a filter on it. Autozone etc sell small filters commonly used on car engines valve covers as a breather that should work just fine for you. just gotta find a way to mount it to keep it from bouncing around. B

He's talking about the breather valve that's on the exhaust headers of California bikes. It injected fresh air into the header near the cylinder head so that unburnt hydrocarbons could be oxidized before they wandered out into the environment. It's what that extra 10 pounds of crap jammed between the header and engine block is for on the Cali bikes.

Blocking off those ports is fine and necessary if you're going to ditch the airbox. Nothing to be worried about. If all that junk is still hanging out behind the headers, you can get rid of that too as it's just dead weight at this point.

Luke-a-Tron wrote:He's talking about the breather valve that's on the exhaust headers of California bikes. It injected fresh air into the header near the cylinder head so that unburnt hydrocarbons could be oxidized before they wandered out into the environment. It's what that extra 10 pounds of crap jammed between the header and engine block is for on the Cali bikes.

They really did that for Cali? Strewth. I mean, sure, it may make a small difference, but won't the extra 10lbs of blubber the engine has to tote around everywhere increase consumption and offset any benefit?

Fartblood wrote:They really did that for Cali? Strewth. I mean, sure, it may make a small difference, but won't the extra 10lbs of blubber the engine has to tote around everywhere increase consumption and offset any benefit?

Haha....this is where the C.A.R.B. (California Air Research Board) is/was misguided. The testing is done stationary..the dyno roller weighs the same REGARDLESS of what the bike weighs...

And, YES< they did that....the reason the hose goes to the airbox was twofold...filtered air AND they get to siphon off any stray hydrocarbons in the airbox with it.

Hell, the Cal. RZs (and buncha other Cal spec 80's bikes) had their tank and bowl vents run thru a CHARCOAL CANISTER about the size of a beer can that weighed about 2 pounds.