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K&N Filter Question - size/shape - which is better (ZX9R

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by robsalvv, Sep 2, 2007.

  1. Hiya folks.

    I see at the knfilters.com website there are two K&N filters for my ZX9R.



    The only obvious difference I can see between the two is the cross sectional area/shape of the filter and possibly the filter medium - but nowhere can I see this stipulated. The filter in the top picture (KA-0021) is more expensive than the filter in the lower picture (KA-9098).

    Which is the higher performance filter. The blurbs don't give any kind of clue. ??

    Appreciate your help.


  2. Hmm... And they're both red.
  3. Most of the KSRC guys will tell you to keep the stock filter, Rob, and just remove the steel mesh that's covering it. It's better than most aftermarkets, apparently.

    I did it on mine, was easy enough to do. I think cleaning it helped more than anything though. ;)
  4. Tenoq, how does the mesh get in the way of the filter?

    Did removing it make any difference to the bike??

  5. Well I noticed a mild improvement, but again, could just be the fact the filter was a helluva lot cleaner afterwards.

    If you look at the mesh you can see it's fairly restrictive in terms of airflow - pulling it off can increase airflow and let's the filter expand a little (which in theory could help it catch more junk?). The general idea though, is that the aftermarket ones aren't enough of an upgrade to justify the cost. Stock one is washable and quite good, so they stick with that one.
  6. I had a chat with Tim from www.superbikesupply.com.au

    Top marks for customer service!

    Basically, what it boils down to is that the first filter, the KA-0021 is as rare as hen's teeth floss in Australia. As far as Tim's official supplier is concerned, they've never imported it. Neither Tim nor his supplier could confirm what the differences betweent he two filters are. I've sent off a note to K&N. Let's see what happens.

    SOOOO, basically, if you get a K&N filter for a 9R, you'll be getting the KA-9098, and as Tenoq said, the guys at KSRC-au.com are all pretty adament that the stocker will be just as good if you remove the mesh.

    I'm wondering though, since the stocker and K&N have different filtering media and K&N guarantee you'll never need to replace it since it's washable, it might still be worth buying a K&N. The stocker has a limited life from what I know.

  7. Having pulled the stock one out and cleaned it, not sure how limited. It seemed pretty durable, and didn't appear to have 'worn' at all after 30,000km. I'd say pull the stocker out and have a look-see - if you reckon it's durable enough, stick with it, otherwise - get the K&N.