bk mod jetting

4 replies to this topic
  • moorespeed426

Posted March 11, 2002 - 08:28 PM


I just did the mod to my 2000426.I set the pump at .3 sec, 168 main, 45 pilot , and raised the clip one notch. I just rode it and the bike runs with the fuel screw in all the way, I know this means to go down on the pilot jet, I was just wondering if this happened to any one else?The temp was about 40, elevation 2500ft. the bike does rev out awesome now!

  • moorespeed426

Posted March 11, 2002 - 08:41 PM


moorespeed426 here again, I lowered the clip one, not raised it.

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  • Rick

Posted March 18, 2002 - 03:01 PM


moorespeed, I'm over in cda and am contemplating the BK mod also, just wondering about re-jetting. did you re-jet just because of the mod before riding the bike assuming that it would run lean, or did you ride it 1st and then decide. I am running stock jetting, should be 162 and 42, and rode probably the same weekend as you (same temps anyway), my bike popped on decel ALOT in the morning (around 35 degrees) but much better as it warmed up. I did not have anything w/me to adjust the fuel screw, but checked it when I got home and it was 2 turns out. I guess that my question really is does the BK mod really effect the main jet circuit? Or does it maybe only effect just off idle on the pilot circut? Sorry this isn't really any help to you, just thought i'd pick your brain a little.

  • h_bomb

Posted March 18, 2002 - 03:15 PM


Try the 42p?Do you run a pipe or stk?If stk try a 165m?

  • moorespeed426

Posted March 18, 2002 - 05:58 PM


I re-jetted the bike frist, I went with the jetting every one else seemed to be using. I have no rode again yet because winter does not seem to want to leave this neck of the woods. I have re-jetted with a 165m and a 42p, and a stock pipe. I agree with Rick that the mod does not affect the main jet circuit to much,my plug was definitely blacker with the 168m verus stock.

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