KLR 650 Airbox Mod

Discussion in 'Thumpers' started by SCouch, Jul 9, 2010.

  1. SCouch

    SCouch Been here awhile

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    Finally getting exhaust, high flow filter and jet kit for the 2001 KLR 650. I've seen some suggestions about drilling holes in the airbox to create air flow, but I'm thinking this will let water in. Is there a way to increase air flow without causing water problems, or is it even needed?
    #1
  2. CA Stu

    CA Stu Steer with your face! Super Moderator

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    Yes and no.

    Yes: the way around it is to cut an "L" in the top of the airbox. You can use a die grinder / Dremel tool to cut it with an abrasive wheel, go slow and you can do a very fine job.

    [​IMG]

    From here: Link

    No: It's not necessary in my opinion. :D Unless you do other mods like a 685 kit and a big valve head, and what kind of dummy would do that to a KLR. :augie

    Thanks
    CA Stu
    #2
  3. SCouch

    SCouch Been here awhile

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    Thanks!!
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  4. WILL_S

    WILL_S OUTLAW POSTIE 001

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    I did mine by drilling 3 1" holes in the top and not cutting the L.You can plug the holes up with rubber grommets to reverse it.
    Did it make a difference ....you bet.Although i have a aftermarket exhaust and different jets & needle height.The mods i did were with the instructions for the pipe to get the best results after fitting the pipe.
    Yep i'm some kind of dummy:evil
    #4
  5. IdaTHUMP

    IdaTHUMP Hunt'n fer sixth

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    A 'stage 1' mod (air, jetting/FI adj., exhaust) will always make a difference in performance but fuel economy will suffer and you will probably be environmentally unfriendly at that point (if that matters to ya...). All in all I am getting away from running my bikes like this the older I get. If you need more power buy a bigger displacement machine!
    #5
  6. Big_AL

    Big_AL Been here awhile

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    I'd did the .22 cent carb mod and Low Buck Exhaust mods on all 4 KLR's I've owned and had great success with just removing the factory restricting grommet from the top of the air box. Got a stack of grommets, anyone need one?:rofl HTH....Al
    #6
  7. Bigger Al

    Bigger Al Still a stupid tire guy

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    I removed the snorkel (or grommet if you prefer) and it made a very nice difference in throttle response.
    #7
  8. Dan Diego

    Dan Diego Long timer

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    #8
  9. SkiBumBrian

    SkiBumBrian DualSport Crazy !!

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    I think it depends on what exhaust you bought and if you want to get the most out of it. If you have a full flow exhaust, go ahead and pull the snorkel. Then perform the L mod but buy some plugs the same size if you think you didn't need to. I say there is a noticeable difference. .. Air in, air out. Its not rocket science. The Lmod holes are under the seat and as high or higher than the snorkel, Were you planning on swimming with your KLR? ;-)
    #9
  10. JBradley500

    JBradley500 Adventurer

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    I did the same thing with (4) 1" holes like Dan Diego plus no snorkel. Even though I really liked those little uni-filters I didn't think they were worth the effort.
    #10
  11. Tsotsie

    Tsotsie Semi-reformed Tsotsi

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    Has anyone done any real before an after, documented testing, to see if this 'L mod', drilling holes actually works?

    People remove the 'snorkle' which has rounded edges to smooth flow the air passing through to a hole with sharp edges and which is not aerodynamically efficient?

    Another of the tribal knowledge gotta haves?
    #11