ZX12R fuelling problem

Discussion in 'Motorbike Technical Discussion' started by Ollie, May 6, 2004.

  1. Ollie

    Ollie Guest

    I've got a fuelling problem with my 2001-model (A2) ZX12R, in that it
    runs far too rich. It's intermittent and you notice it as it runs
    jerkily or unsettled at light throttle just bumbling along at 30 - 40
    mph. Get off the bike and stick a finger in the exhaust pipe exit and
    it's covered in a really thick, powdery layer of soot (much heavier
    than normal). This first started happening shortly after the bike was
    new, about two years ago. The dealer had it back in but never really
    traced the problem (although they absolutely agreed that the fuelling
    was miles too rich). They replaced lots of parts, including ECU,
    sensors and injectors. And that SEEMED to cure it (although it was
    intermitent anyway). But, two or three weeks ago I was out for a ride
    and suddenly it was running unsettled and making piles of soot in the
    exhaust - and using lots more petrol than usual. Up to its old tricks
    again. Any ideas out there? By the way, it's had its plugs replaced
    (and has run like this on three sepaarte sets). And I use a variety of
    brands of petrol - not from just one petrol station.
    Ollie, May 6, 2004
    1. Advertisements

  2. Ollie

    DaveInOttawa Guest

    post it to the ZX12R.org site... www.zx-12r.org

    but just curious, do you have any air intake restrictions? An
    intermittently collapsing inlet on the air side would cause a intermittent
    rich condition. And it's something that might not be readily apparent on
    the bench.
    DaveInOttawa, May 6, 2004
    1. Advertisements

  3. Ollie

    Ollie Guest

    Hi Dave. Ooops, is there a dedicated ZX12R group, then?! Didn't
    realise. Thanks.

    As far as I know, all the bike's airways are spotlessly clean. No dead
    pigeons or anything! The bike's up on my jack at home right now.
    Airbox inspection covers are off, air filters are out, rubber ram air
    duct sections are off. In other words, you can have a good look
    through the ram air ducts and airbox. And they're all clean. Airbox is
    a tiny bit oily inside but not puddles of oil. Air filters now a bit
    dirty-looking (I've done 20k miles) but not clogged. Anyway, I've
    cleaned them up as usual (what's good for cleaning this type of
    filter?). I also took off those dangly ram air "bottles/reservoirs"
    which plug into the ram air duction just behind the leading edges of
    the R & L main side fairings. They just plug into a grommet. They have
    small drain holes right at the bottom. Both R & L reservoir drain
    holes were blocked, so I cleared them. They're all part of the
    resonance of the intake air ("gas dynamics" and all that stuff). But
    can't imagine that blocked drain holes and quarter of an inch of
    collected rain water in the bottoms would ruin the fuelling. Spark
    plugs ar also out. OK, so they're very sooty but I already know the
    bike's running rich and would expect sooty plugs. Oh yes, is there a
    good way to clean spark plugs? Your average bike shop geezer will
    always say just to buy new ones (at over 50 quid a set!). As for now,
    I sort of feel that it might be an electrical fault causing the
    problem. So, as the workshop manual suggests, I'm trying to test the
    outputs from the various sensors and also checking the relevant bits
    of the harness for continuity (although the ECU never logs a fault and
    reckons that everything's healthy). The trouble is with all this
    testing is that you've got lots of voltage values in the manual which
    you're trying to check. In an ideal world, it's all very simple.
    Batteries make 12 V (under ALL conditions) and connections/wires have
    always got ZERO resistance across/along them. Rubbish! You get the
    picture?! I'll end up with piles of numbers which aren't quite 12 or
    aren't quite zero. And off I'll go to the dealer with a huge shopping
    list. New battery, new harnesses, new sensors, new switches, new
    alternator, new regulator/rectifier, etc. Except I won't!!! I'm not a

    No, the most weird thing I've uncovered from looking at the Internet
    to research my fuelling problem is something that's well reported on
    www.zx-12r.org. Crankcase pressure is forcing engine oil up the
    harness going from inside the LH engine casing (where the alternator
    is) and it's collecting inside one of the regulator/rectifier
    connectors. But, the oil isn't just going inside the external harness
    sheath - it's travelling along the actual stranded conductors in the
    wires. So, you don't really see anything wrong from outside. But quite
    a lot of oil is collecting inside this connector. I unplugged mine and
    a teaspoonful of engine oil poured out!!! Kawasaki have an official
    recall on the problem, but their free fix misses the point and cures
    nothing. They externally wrap the harness near the connector with
    tape. But the oils right in the core of the wires and passed beneath
    all Kawasaki's free tape!

    Cheers, Dave. I'll have a look at that ZX12R group. Ollie.
    Ollie, May 7, 2004
  4. Ollie

    Ollie Guest

    Dave, Dave, Dave!!!!!! I'm blind! The site you mentioned is the one I
    already know about!!!! I'm even mentioning it in my first reply,
    written a few minutes ago!!! Doh!!! Should I really be riding a
    ZX12???!!! Just got into work and I'm still half-asleep! But, yes,
    I've rambled on about my fuelling problem on www.zx-12r.org, but it
    seems to be a one-off. Trust my luck!


    Ollie, May 7, 2004
  5. Ollie

    DaveInOttawa Guest

    well... you've got me shaking my head, Ollie, especially with no fault codes
    and the changes you already mentioned in your first post. Seems you've got
    the gurus on zx12r.org baffled too.

    And yes, I was aware of the recall on the stator wire connector... mine was
    absolutely dry, but replaced anyways under warranty.

    What does Kawasaki offer you? Like you, I'm not rich either, especially
    with the appetite the 12R has for rear tires. Have you contacted their
    regional office?

    Good luck.
    DaveInOttawa, May 7, 2004
  6. Ollie

    Geribaldy Guest

    Try asking on www.200mph.org
    The 12 riders there are quite knowledgeable, and there are some top quality UK tuners there too.
    Geribaldy, May 7, 2004
  7. Ollie

    Ollie Guest

    Hi Geribaldy. Thanks for that. Will have a look.
    Ollie, May 10, 2004
  8. Ollie

    Ollie Guest

    Hi Dave.

    So, did Kawasaki actually replace the whole harness for you? Are
    recall fixes potentially different in each country? The fix here in
    the UK was just to wrap some insulating tape around the harness where
    it goes into the regulator/recifier connector/plug. Maybe Kawasaki is
    more scared of upsetting you guys than us British!!! You get a shiny
    new harness, and we get a bit of sticky tape!!!!!! Got to laugh (until
    I remember that my bike is still up on a stand in the garage, with
    wires hanging out and surrounded by spanners and voltmeters)!

    And this alternator harness issue isn't even my main problem! Still
    got to get to the bottom of my fuelling problem. Of course, I dream
    that I'll fix the oily harness thing, put the bike back together - and
    magically it will have sorted out the fuelling thing too!!! Dream on!

    Still, I love the ZX12 and am looking forward to our UK weather drying
    up and heating up a bit in the coming months. Recently has been OK
    because we've had some mega downpours. I just tell myself that it's a
    good thing that the bike's in bits as I would have got saturated if
    I'd been aboard! But fuelling problem or no fuelling problem, I'm
    going to enjoy my riding this summer!
    Ollie, May 10, 2004
  9. Ollie

    DaveInOttawa Guest

    My connector was dry... some others had reported crankcase oil "pouring" out
    of the stator plug. I don't know if mine was actually replaced, but I did
    open it up to inspect, and it seems to be sealed with some epoxy-type stuff
    at the bottom of the plug (where the wires feed into the connector). I
    don't know if this was the warranty fix or not, but it seems to be holding.

    I wish I knew some magic fix for your fuelling prob... an intermittent rich
    condition is a b!tch to solve on a bike with FI, especially with the
    computer not returning any fault codes. Have you considered a
    PowerCommander III??? That will bypass the stock ECU for the fuel mapping,
    and is tunable? You also didn't mention any mods (pipe, etc)... If you
    don't have a buddy with a PC-III, you might find one on e-Bay... I've seen a
    few there.

    Good luck.
    DaveInOttawa, May 10, 2004
  10. Ollie

    Farmer_Owe Guest

    Dude,jst go n c a dealer n get warrenty...if u were smart enuff 2 get
    it with a expansive bike like dat.....u did didn't u???
    Farmer_Owe, May 11, 2004
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.