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VTR air filter questions

Discussion in 'Riding Gear and Bike Accessories/Parts' started by toodles, Sep 5, 2005.

  1. Are there any decent aftermarket air filters available for a 2001 VTR250?

    I've heard you need to retune the carby after upgrading the air filter to reallyu optimise perfoirmance but will it make it run any worse than a normal filter if I upgrade the filter but don't retune the jets?
  2. If you install a less restricted filter the mixture will be lean because more air is passed to the jets. If you now increase the jet size to let more fuel through you will re-balance the fuel/air mixture. Since we now have both more air and more fuel in the correct proportions we get a bigger bang.

    If we increase only the air by changing the filter alone we end up with a lean mixture that over time could put a hole in your piston.
  3. hmmm.... I'm having trouble finding an aftermarket air filter manufacturer that has bothered to make a filter for the VTR so I might just replace it with a stock unit.
  4. Nothing on the K&N website??
  5. K&N soooooo make one for the VTR thou!
    Bikes are tuned from factory to run very rich.
    The difference in a K&N replacement filter in terms of flow would only be marginal and it would make your bike run noticeably better as the mixture is slightly leaner.
    I had a reputable tuner fit one to my Hornet and it runs better than before and has better acceleration.
  6. Most bikes, when standard tend to be tuned on the lean side, in an attempt to pass emissions laws.

    The VTR 1000 must be an exception.
  7. Hmm looking above... EFI will deal with the new filter by its little brain... but the carbes.. need will need a human hand... some bikes will reqire jets some needles and some a twist with a screw driver... every bike model is different...
  8. Do you really think that a major manufacturer would risk running an engine even slightly lean?! :shock: I think not.....
    Put just about ANY factory standard bike on a dyno, have the probe in the exhaust and you will see RICH A/F ratios.
    One of us has to be right...... :x :LOL: :LOL:
    Daz. :wink:
  9. But none for the VTR 250 as far as I can see or find.

    If anyone has found an aftermarket filter for the VTR250 (hope the filter design hasn't changed from year to year) let me know. The stock Honda one is around $82 from what I've been quoted.
  10. how dificult would it be to make one?? I have made one for the CBR250RR and a FZR250??
  11. Brand and part number, please??
  12. Keep in mund you will have to drill the slide vent out too. Filters tend to upset the immediate on-throttle vaccum on CV's and the vent hole in the bottom of the slide needs to be increase to help it come up.

    Usually 2.3mm

    As for the lean vs rich thing, it varies from bike to bike. Because of the vaccum thing you may find you will need to run leaner down low. I went down 2 jets sizes on mine.

    You will likely need to increase you main jet size. This is the jet manufactures run lean to pass emission laws, because they know most people ride on the needle

    The needle hight will definatly vary depending on your bike and setup