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450 stage 2 cam and hi compression piston jetting question.
  • Jimbo0909
    Posts:25
    Joined:Thu Mar 05, 2009 9:18 pm
    450 stage 2 cam and hi compression piston jetting question.

    by Jimbo0909 » Tue Apr 13, 2010 9:16 am

    just put a 12.5:1 hi comp piston in my 06 450R runnin a 185 main jet and a 48 pilot with the stock fuel mixture screw setting and needle setting and its still running lean. anyone else running this setup?
  • Asmith
    Posts:14381
    Joined:Mon Apr 10, 2006 7:52 am

    by Asmith » Tue Apr 13, 2010 11:09 am

    Where is it lean?? Did you do a plug chop?
  • Jimbo0909
    Posts:25
    Joined:Thu Mar 05, 2009 9:18 pm

    by Jimbo0909 » Tue Apr 13, 2010 5:42 pm

    yeah i did a plug chop and its still running lean i just got a 50 and a 52 pilot so im gonna try that and see what it does
  • Asmith
    Posts:14381
    Joined:Mon Apr 10, 2006 7:52 am

    by Asmith » Tue Apr 13, 2010 5:52 pm

    Shouldn't need anything bigger than a 48 at the most...usually a 45 works great with the 450R's.

    Make sure the passageway between the pilot/fuel screw and the venturi is open and clean.
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    wmrice
    Posts:75
    Joined:Sun Apr 08, 2007 3:15 pm

    by wmrice » Tue Apr 13, 2010 7:54 pm

    What needle are you using? My 450x is running a stage 2 and a 13:0-1 piston and I'm only running a 172 main JD red needle and a 45 pilot and it flys with that set up
  • dsrpilot
    Posts:251
    Joined:Wed Sep 30, 2009 10:12 am

    by dsrpilot » Tue Apr 13, 2010 8:11 pm

    Ok, I give. What's a plug chop?
    '12 CRF450X - son
    '09 CRF250X and 2010 F800GS lowered - Wife
    '12 CRF250X and 2012 F800GS - me
  • Asmith
    Posts:14381
    Joined:Mon Apr 10, 2006 7:52 am

    by Asmith » Tue Apr 13, 2010 9:03 pm

    dsrpilot wrote:Ok, I give. What's a plug chop?


    Killing the engine at a certain RPM and immediately pulling the plug to see it's condition.

    Riding wide open to see what the plug looks like won't work if the bike idles back to the truck afterwards...
  • dsrpilot
    Posts:251
    Joined:Wed Sep 30, 2009 10:12 am

    by dsrpilot » Wed Apr 14, 2010 4:48 am

    ~ wrote:
    dsrpilot wrote:Ok, I give. What's a plug chop?


    Killing the engine at a certain RPM and immediately pulling the plug to see it's condition.

    Riding wide open to see what the plug looks like won't work if the bike idles back to the truck afterwards...


    Thanks. Learning something new here every day!
    Gotta love it... 8)
    '12 CRF450X - son
    '09 CRF250X and 2010 F800GS lowered - Wife
    '12 CRF250X and 2012 F800GS - me
  • Jimbo0909
    Posts:25
    Joined:Thu Mar 05, 2009 9:18 pm

    jetting

    by Jimbo0909 » Sun Apr 18, 2010 12:32 pm

    put a 50 pilot and a 190 main with my needle on the 5th position now it runsd great.
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