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Carby overhaul = valve job on ZZR250

Discussion in 'Bling and Appearance' started by Noticibly F.A.T, Feb 18, 2008.

  1. Can someone please give me an idea on the cost of one of these?

    Bike is a ZZR250. Bought it 3 weeks ago. Took it in for its first service. It was running lean, and i knew this. Thought it just needed a carby tune-up. Had a sponge in the air intake to prevent it lean-ing out until service date. Was running (what seemed to be) fine, apart from a slight lack of power (but arn't all 250's like this?)

    This is my first bike, so i am unsure. But compared to the CBR250R and the FZR250 i rode, they were definately faster, and top end they had more power.


    Took my bike in for a service, and apparently the old air filter was so old the carby sucked little bits in to it, and the carby needs a full overhaul.

    Including the cost of a service its going to cost apparently $580
    Thats not including if the carby needs any internal parts replaced.

    Am i being taken for a ride? (excuse the pun)

    I know the carby is a Keihin CVK30. The dude at the shop said they cost around $1000 brand new.

    Can anyone please please please help me! I need to know if i am being stooged or not. I hope i'm not, as its a very reputable workshop. I assume most of the cost of the $580 is labour to find the problem? Not sure.

    Any help whatsoever is greatly appreciated!
    Thankyou - Luke
  2. Re: Please help! Carby overhaul on a ZZR250

    The carbs would not need an overhaul just because they sucked bits of aircleaner element and sent them into the engine. The carbs might need an overhaul because they are oldish.

    It is more likely that the engine is harmed a little by the foam and dirt which it would have ingested, via the carbs. Are they quoting to repair this?

    Can you itemise or reproduce the quote? Best to get it in writing, even if they are a reputable joint.

    Something as obvious as a sucked in aircleaner elephant should not take all that long to identify. Don't get sucked in yourself.

    All the best

    Trevor G
  3. Just spoke to them then. Was a different guy, but he said service is about $200 - $220.

    So that means about $360 to strip and re-build the carby's.

    Does that sound right?

    EDIT: Just got a quote for 2 brand new carbys from a geniune kawka dealer. $1,417 for the pair of them....
  4. They opened up the carbys, and.... they are fine. He said they actually look really really good.

    So no problems there. They are checking the valves now. Hopefully its a valve clearences issue or something, and its cheap to fix.


    Thanks for your help anyway trev! :)
  5. That's a good sign that, like most other dealers, yours can be trusted.

    Most shop/businesses are so busy that they don't need to load service jobs. I wish some of the other posters here could see that point. :)

    All the best with the rest of the probs, and let us know what they did.


    T G
  6. Ok. 1 of the valves in 1 of the cylinders needs to be "shimmed" or "faced" Its letting exhaust gas back in when its fully closed... No wonder it was flat spotting.

    They are gonna "face" all the valves in both cylinders though, make everything even. Tune the carby again, and put new gasket seals on the head, and new 0 ring seals on the bolts and all that jazz.

    Unfortunately, they don't "face" the valves there, its done off site, so turn-around time is 1 week minimum! Although if i need new valves (if they can't be faced, cause there isn't enough valve left) then they will just order some from kawasaki.

    Either way, its about 2 - 3 weeks for me without a bike :(

    BUT, when i get her back she will be running like a dream!!! I can't wait!!!

    Thanks again for your post Trev mate! :)
    Cheers - Luke
  7. They are having to "grind" or "face" the valves because they haven't been checked frequently enough - every 10,000 km or so, I imagine. That is the "shimming" part.

    A shim is a very precisely measured thickness of hardened steel which is inserted between the valve stem and the camshaft on some OHC bikes. To adjust the valves the shims need to be changed for ones of a different size.

    Because some folks don't know how to obtain them, or are just too lazy to even check the adjustment, they get left. The adjustment eventually closes up so much that the valve stays partly open and, especially in the case of the exhaust valve, starts to burn out the very finely machined surface which closes off the exhaust port.

    This reduces compression and combustion efficiency. Find the correct service interval for valve checks and either do it yourself, or get it done by a shop. Especially after a valve job, the adjsutment should be checked much sooner than usual, just to be on the safe side.


    Trevor G

    PS Just for clarity can I suggest you change the post Topic to "Carby overhaul = valve job on ZZR250" - that makes it even more appealing and informative.
  8. Thanks for that Trev. Yeah the bloke at the bike shop explained what facing was. I already knew how valves work on OHC engines. Didn't know thats what a shim was though!

    Thanks again mate - Luke

    p.s I'll keep you, and anyone else reading posted on what's happening with her, so if anyone else gets a problem like this, just link them to it! :)