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BEC REED VALVES????????????
tilly819 - 31/1/10 at 11:14 AM

hi all, i have almost finished my super blackbird roadster now,

one quick question
should i uncover, remove or blank off the reed valves on the head also which ever it is why do i do it just so i am awere

im hoping i can blank them off since they make quite abit of noise and im still abit above 99DB i think i have managed to get the exhaust noise down but now the engine noise is coming into play kinda like high ambient...

chears tilly


mistergrumpy - 31/1/10 at 12:12 PM

I think the reed valves are part of the EGR system, or at least they are on the ZX9's. I've just connected them together with a pipe on my engine. I know Hellfire's blanked theirs off.


Hellfire - 31/1/10 at 02:39 PM

We manufactured some billet aluminum reed valve chamber block off plates. They are designed to safely block the reed chambers after removal of the Kleen air system (Kawasaki Low Exhaust Emmisisions)

The kleen air system on the ZX12R, is there to add more air (oxygen in particular) to keep the exhaust gases burning longer as they travel through the system thereby depleating more of the hydrocarbons for emissions purposes.

The exhaust flow has a negative pressure at certain points in the cyclical flow which "suck open" the reed valve allowing the outside air into the port. When the pressure in the port goes positive the reed valve closes preventing exhaust from flowing back into the inlet system.

Unfortunately this system can also cause backfiring when aftermarket exhausts are fitted, so some people just remove the kleen air system altogether and blank the chambers off. It is also claimed that there is a slight increase in BHP to be had but this is debatable.

Either way, it removes some unnecessary weight and makes for smoother engine running.

Phil


eddbaz - 31/1/10 at 02:57 PM

Mine are blanked off on my zx12r the same as hellfires but I only did this after the sva as the clean air system had to be fitted in order to get the emissions to the required pass rate.


Hellfire - 31/1/10 at 03:16 PM

Thats a valid point that Ed has made. You may want to keep the Blackbird PAIR system on for emission purposes at IVA.

Ed, did the Kleen air system need to be fitted to yours to pass SVA? Did you do a before and after check on the emissions?

Phil


G.Man - 31/1/10 at 05:19 PM

Mine passed with the reed valve plates blanked off.


Hellfire - 31/1/10 at 08:16 PM

quote:
Originally posted by G.Man
Mine passed with the reed valve plates blanked off.


Yeah, there's been a few others too. Just wondered how much of a difference the kleen air system actually makes to emissions........

Phil


tilly819 - 1/2/10 at 10:48 AM

thats cool guys thanks,

hopfully i have blanked them off probly need to make some propper blanks like the ones in your picture above,

i have fitted a good CAT for IVA so hopefully emissions should be ok, ither way its going to the garege this weekend for a brake and emmisions test #]

chears tilly


G.Man - 6/2/10 at 02:54 PM

quote:
Originally posted by Hellfire
quote:
Originally posted by G.Man
Mine passed with the reed valve plates blanked off.


Yeah, there's been a few others too. Just wondered how much of a difference the kleen air system actually makes to emissions........

Phil


It gets the cat hotter so can see a reduction in HC and also some reduction in CO where there is a rich mixture.