Jet needles
  • User avatar
    TRD
    Posts:38
    Joined:Mon Dec 07, 2009 11:17 am
    Jet needles

    by TRD » Mon Oct 11, 2010 8:57 am

    I´m having a needle issue. Modified CRF250R 2009 engine and I need to change different needle. Is there any translator what Honda needle codes mean?
    Example stock needle is NNTU. What are specs? Keihin uses own codes which seems to be different. Anyone can help? I can order from honda too needles but catalog only inform their codes.

    Cheers,

    Timo
  • User avatar
    n2stackin
    Posts:67
    Joined:Mon Aug 09, 2010 7:26 am

    by n2stackin » Mon Oct 11, 2010 12:42 pm

    ok, maybe this will help. page 127 talks about standard jetting and altitude. page 128 talks about a modified engine.

    http://www.hondamc.com/upload/Download/CRF250R9%20Instruktionsbok.pdf
    2004 CRF250X (my bike)
    2004 CRF150F (girls bike)
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    crfsonly
    Owner
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    by crfsonly » Mon Oct 11, 2010 5:15 pm

    I'd highly recommend getting the JD Jetting Kit. It includes two needles that have been custom tapered specifically for the CRF250R. Here's a link:

    http://www.crfsonly.com/catalog/product ... ts_id/2657

    ken
    OEM Parts for Honda - Yamaha - Suzuki - Kawasaki: http://yeltrik.com
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    CRF Parts and Accessories: http://crfsonly.com
  • User avatar
    TRD
    Posts:38
    Joined:Mon Dec 07, 2009 11:17 am

    by TRD » Tue Oct 12, 2010 4:20 am

    Thanks but those wont really help me. I have Honda manual and it tells NNTU is right needle but it´s not.
    I have right jetting allready so I don´t want to spend money for JD Jetting Kit because it´s not sure that it will work.
    I know what I need when I see information about NNTU needle but it´s difficult to measure needle accurately.
    I drive enduro and my 2009 CRF250R has lower compression ratio then stock and different camshaft timing. Engine is milder and not so much snap on it then stock. Power comes up in lower rpm. So that´s why the needle problem.

    - Timo
  • User avatar
    n2stackin
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    Joined:Mon Aug 09, 2010 7:26 am

    by n2stackin » Tue Oct 12, 2010 6:30 am

    Email or call the shogun, James Dean himself. He is a nice guy and can probably help you without trying to sell you something. If you can't find what you need by checking the forum, googling it, or calling your local dealer, that is my suggestion.
    2004 CRF250X (my bike)
    2004 CRF150F (girls bike)
  • Asmith
    Posts:14381
    Joined:Mon Apr 10, 2006 7:52 am

    by Asmith » Tue Oct 12, 2010 7:16 am

    OK Timo,

    here's how the lettering system works. Let's compare two commonly used needles in the CRF's, the NCVS and the NCVU.

    The NCVU is leaner than the NCVS.

    The lettering system works like this:

    After the N, the first letter is the taper. "C" so they are both the same taper.

    The second letter is the clip postion relative to the top portion of the taper. They are both V. They get leaner as you go up thru the alphabet towards Z.

    The third letter is the needle straight diameter.The S is richer than the U. They also get leaner as you go up thru the alphabet towards Z.

    Hope that helps.
  • User avatar
    n2stackin
    Posts:67
    Joined:Mon Aug 09, 2010 7:26 am

    by n2stackin » Tue Oct 12, 2010 7:22 am

    or... AS can answer.
    2004 CRF250X (my bike)
    2004 CRF150F (girls bike)
  • User avatar
    TRD
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    by TRD » Wed Oct 13, 2010 12:33 pm

    All I ever wanted to know :) Thanks a lot all of you!

    - Timo
  • User avatar
    TRD
    Posts:38
    Joined:Mon Dec 07, 2009 11:17 am

    by TRD » Wed Oct 13, 2010 1:10 pm

    Ok no I´m buying NNTS needle place of NNTU.

    If we compare NNTS needle and AS mensioned NCVS needle result is.

    NNTS taper angle is bigger than NCVS

    NNTS length diameter is smaller than NCVS

    NNTS needle straight diameter is the same than NCVS

    Does all those Honda CRF needles fit apart? If I rememer right older CRF´s have little bit different FCR Keihin on it.
  • Asmith
    Posts:14381
    Joined:Mon Apr 10, 2006 7:52 am

    by Asmith » Wed Oct 13, 2010 2:03 pm

    The older needles will fit the newer carbs without issue.

    The newer needles will need the new holder assy to fit the older carbs.

    Since you have an 09, any needle will fit without issue.
  • User avatar
    TRD
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    by TRD » Wed Oct 13, 2010 9:29 pm

    Cheers! I believe right setup will find now.

    - Timo

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