RICH OR LEAN????



3 replies to this topic
  • screamin426

Posted December 15, 2001 - 04:22 AM

#1

HEY ALL,

WHAT ARE SOME SIGNS THAT YOUR BIKE IS TOO RICH OR TOO LEAN? ARE THEY SIMILAR TO 2-SMOKE SIGNS(BOGGING ETC)I'M GOING TO PLAY WITH MY JETTING AND WAS LOOKING FOR A HEADS UP...THANKS :)

  • bbeakley

Posted December 15, 2001 - 02:23 PM

#2

Your idle circuit is too lean if you get some decel popping and a hanging idle. If you're too rich it'll be tough to start most of the time and bog. Try to choose a pilot jet that will be set up right when your fuel screw is about 1 3/4 to 2 turns out, that will allow you to adjust for temperature with the fuel screw without changing jets. I'm not sure how to tell if you're lean up top. Most of the replies I've heard on here tell you to up the main jet until it starts blubbering at high RPM then back off one size. There is some debate, but a lot of people say that the plug isn't a good indicator of the jetting unlike a 2 smoke.

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  • Fastest1

Posted December 16, 2001 - 09:07 AM

#3

I would agree with Bbleaky. However I do believe in plug readings. The insulator and tip give you an idea of main jet size. I like to run mine a light tan.The outer jacket (steel threaded portion) will give you an indicator of the slow jet. If it is sooty you are too rich. I have used slow jets #48 & #45 my bike starts 1st kick with no choke with the BK mod. I do not foul plugs at all anymore. I do notice a small amount of popping on decel with the #45 but I am trying to use the mixture screw to eliminate it. Good Luck and try to experiment a little and find out for yourself. I run a 2000 426 stock except a Uni Filter. Its jettings at the moment are a 170mj,45pj,Obekr needle 4th clip from bottom, Bk mod @ approx .2-.3 seconds, airscrew about 1&1/2-1&3/4 out. I am at sea level or at the moment maybe even below it LOL (lots of rain lately which I would gladly ride in however the tracks are all closed(wimps). How do you get better in mud if nobody lets you ride in it? Cya :)

  • Fastest1

Posted December 16, 2001 - 09:08 AM

#4

Sorry for the typo Bbeakley :)





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