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K & N AirFilter for a CB250F Hornet

Discussion in 'Bling and Appearance' started by VCM, Feb 19, 2008.

  1. Hey Guys ... could someone help out here plz
    I'm told K&N dont list an air filter for the 250 hornet :cry:
    However I read somewhere that the CB600F share the same filter.
    Can anyone verify this?
    Thanks in Advance

  2. Can't help with your question but will add:

    You do realise, don't you, that by itself, a K&N replacement oem-style element does not add any additional airflow over a standard paper element in good condition, that will give a measurable power increase?


    Trevor G
  3. How so? They do for cars.
  4. There have been a number of tests over the years.

    The one I liked showed that there was no real difference in airflow which produced a measurable increase in HP. A standard, folded paper element has a much greater surface area than a K&N replacement.

    It's different if you replace the original airbox and fit pods straight to the carbs, or if you open up the restricted airbox.

    However, in the latter case, you can do that with the original aircleaner element in place and still see good gains.


    Trevor G

    PS Obviously, to comment, I have also tried these "improvements" myself and that's when I was disappointed to find that my money was wasted as a performance enhancement.

    PPS If there was a difference you would have to remap or rejet when changing element brands or types. In practise, you don't.

    Fitting pods or opening up the airbox is a different matter... ;-)
  5. I've heard the same thing as Trevor.

    But you will get 100,000k's out of them before having to clean them up.
  6. A K&N will need cleaning long before a folded paper element, because it does not have anything like the same surface area.

    A K&N has bigger "holes" in it which let more dirt in. If you only ever ride in a dust-free environment then they are OK.

    I have K&N pods on my guzzi because they were there when I got it, and they look kinda nice. Also the oem airbox is the most amazing piece of awful plumbing you have ever seen. ;-)


  7. I have a K&N in my car also, hard to say if it improved performance.
    Perhaps I may stick to the standard type for the hornet .. not sure :?
    Thanks the for input Guys :wink:
  8. Fair call Trevor! It says 100,000k's on their marketing stuff I've got at home.
  9. Yep, and they're usually biased to achieve a desired result.
    K&N test theirs to the SAE/ISO standard - I've not seen any data from such a test showing an increased airflow using paper.
    In fact paper isn't that great as a filter media for the simple reason that there's little control over the arrangement of the fibres so to prevent large holes you have to have a shiteload of tiny ones - which restrict airflow.

  10. I think the reverse finding is just as important - the difference in airflow for a K&N over a standard folded paper element is not large enough to provide measurable gains and/or hp improvements in independent testing.

    A K&N also isn't as effective as foam in a dusty environment, but most of us don't ride dirt bikes. Neither are as efficient at removing dust as a folded paper element, but paper can clog relatively quickly in really dusty conditions and then perforate, dumping dust through the engine.

    For me, on country roads (gravel) with a diesel. being able to go 20,000 km before servicing the foam element (a very messy and time consuming job) meant a lot. Under the same circumstances a paper element could be clogged in 5,000 km.

    Certainly when I pod my latest Guzzi Lario I will use a K&N, but not because it works better than a Unifilter - I don't believe they do - I prefer the K&N look to the green foam look. :) And it seems most road bike riders agree.


    Trevor G

    PS Removing the airbox and its restriction is when most K&N owners see a difference.
  11. True, but then K&N don't make overly ambitious claims when it comes to hp - only claiming 1-4hp on car engines translates to 1% or less which you're not going to notice.

    And I agree that different filters are better for different situations. I prefer K&Ns in my car simply because they clog less easily and yet still pass ISO standard for filtration. But I'm sticking with the OEM oiled foam in my bike simply because it is easier to clean (and K&Ns for bikes are stupidly expensive).