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Cam Cover ZL600

Trojan441 May 15, 2019

  1. Trojan441

    Trojan441 Well-Known Member

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    Have an 86 ZL600A engine to rebuild and noticed the Cam cover is different to the ZL400, having 2 vented box structures attached to either side, what r these for, pollution control ?
    kawasaki-zl600b2-eliminator-600-1996-usa-california-cylinder-head-cover_mediumkae0250e1112_9a7b.jpg
    Plus any chance of ever getting a ZL 600 microfiche parts list?

    Also on road tests, i generally found any USA stuff generally is listed as having less Bhp than model imported here in Europe but particularly the UK.

    ZL 600B regularly lists as 60 Bhp, but the ZL600 A was rated @ almost 74 bhp1 Neither 398cc engines I have, display this feature!


    Cheers


    John H
     
  2. Trojan441

    Trojan441 Well-Known Member

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    https://www.cmsnl.com/kawasaki-zl600a

    Found this site above and just found out the Cam Box cover on mine is off a Califonian model! Now, checking engine number with VIN to see what i have got in my box of bits! Hope the engine if from USA hasn't been "wimperized too much by the EPA!

    Cheers

    John H
     
  3. Trojan441

    Trojan441 Well-Known Member

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    Yep!
    Bike imported to UK in 1998, ( forgot ZL600 A never imported here in the UK) only ZL600 B in the 19900s, the Naff-looking model! ZL600 A is of 1986 manufacture, so it obviously started life in California n' ended up in rainy old Britain, poor thing!


    Maybe a silly question, but I guess i can just blank those pollution features off/


    Cheers


    John hall
     
  4. 87kawzl

    87kawzl Supporting Member

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    12021 is a Reed valve for crancase fume recirculation (emissions system). When you block off those you need to make sure your crancase is vented. Mine has a small filter off the nipple on the cover on the left side top of trans.
     
  5. Trojan441

    Trojan441 Well-Known Member

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    Okay, thanks, I had read about Californian machines having sealed fuel systems, isn't there a vent on Kawasaki engines too, that goes back into the air-box by a small pipe from the transmission housing at the rear of the engine?

    Those reed-valve boxes do not seem to connect through the Cam cover as at first I thought they might!
     
  6. Trojan441

    Trojan441 Well-Known Member

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    Beware buying "Basket case" bikes. Unpacked the box supposed to have all the cylinder head bits in it & at present camshaft bridges 3 & 9 are missing!
     
  7. Trojan441

    Trojan441 Well-Known Member

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    Spoke too soon found them, ever had a joyful feeling for a few seconds!
     
  8. 87kawzl

    87kawzl Supporting Member

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    That's awesome, I know the feeling!
     
  9. Ed

    Ed Active Member

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    The crankcase is vented separately under the box so plug the hole in front and manifold nipples.
     
  10. 87kawzl

    87kawzl Supporting Member

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    Mine has no airbox left, in that case a 2" filter is used for crankcase ventilation.
     
  11. Trojan441

    Trojan441 Well-Known Member

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    When I said I couldn't see how they were vented, the Reed valves, I had picked up the Non- Reed valve Cam cover by mistake n' completely missed the four vented tubes on the Reed valve Cam cover, until I looked @ the stuff again Non-Reed valve n' Reed valve Cam covers!

    Does the vented Cam cover affect the engines performance when connected up?
     
  12. Trojan441

    Trojan441 Well-Known Member

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    Must have been "DUH" moment!
     
  13. 87kawzl

    87kawzl Supporting Member

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    I doubt the performance will be changed a whole lot with or without the emissions crap.
     
  14. R. J.

    R. J. Supporting Member

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    :hello: Some of us have removed the Emissions from our ZLs and put on block off plates or a valve cover from Europe. I think my bike runs better with the Emissions removed.
     
  15. Trojan441

    Trojan441 Well-Known Member

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    I was always taught & worked on the Principle that the cleanest coolest draught of air you could get in the inlet port was the way to getting the Sweetest running engine out there!

    I remember how much sweeter a 175cc two-stroke single ran hen the air was cold n' crisp in our old fashioned winter times. It was like a super-charger had been fitted! Trouble was to take advantage of the better performance meany riding on potentially icey Country roads! Also getting cold hands n' feet, but worth it as a 17 year old who imagined he was King of the road! We had decent fuel then too, 1974/75.
     
    R. J. likes this.
  16. R. J.

    R. J. Supporting Member

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    :hello: My 1978 440 Yamaha Exciter air cooled 2 stroke twin snow machine seemed to make more power when the temp was below 0*F. When the snow was not deep enough for my sled I used to ride my 1978 Yamaha DT 175 also a 2 stroke on the snow covered roads & in the woods all Winter long. Like you said at 17 you feel indestructible.
     
  17. Trojan441

    Trojan441 Well-Known Member

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    Two-strokes take advantage of the incoming cold drier air so the cylinder/cylinders fill with a denser better draught/charge of air n' fuel = more power YA! 4 strokes just seem to run a little cooler!
     
    R. J. likes this.
  18. Ed

    Ed Active Member

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    The reed valves have nothing to do with crankcase gases. They get fresh air from the airbox when the throttle is closed so the unburned hydrocarbons of the oxygen-deprived mixture entering the exhaust get extra oxydant to help complete the burn and produce less harmful emissions. Since it only kicks in when off throttle, there's no change in performance but they fail and can leak air into the intake manifolds. Mine did so I plugged the vacuum lines with steel balls so it all looks stock. The charcoal canister doesn't hurt power either.

    The retarded ignition timing which decreases NOX is the only emissions related thing that decreases power and causes hotter running conditions. Advancing the timing on most engines sinces the 80's has been a common upgrade.
     
  19. Ed

    Ed Active Member

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    4 strokes have the exact same power increase. Difference is that extra power is offset pushing the cold, thick oil around.
     
  20. Trojan441

    Trojan441 Well-Known Member

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    AS far as I understand the Ignition timing is pre-set on the ZL's in the wizard trickery of the igniter unit. Short of altering the spark plug gag i thought there is nothing else u can do!
     

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