Whacking = Off What's the Cause?

5 replies to this topic
  • RichB

Posted March 26, 2002 - 10:44 PM


Alright guys, I know the Bog/BK issue has been discussed to death but I don't remember seeing anyone saying what causes the bike to bog or outright stall when you chomp on the throttle hard. i.e. low speed wheelie or in neutral whacking the throttle.

Is the bike starving for fuel or is it getting too much gas?

If it's starving for fuel how does shortening the pump duration (via BK) alieviate the lean condition?

If it's a rich condition I assume that because you're subtracting so much fuel by decreasing the duration that you can go up a pilot and still be leaner than without the BK adjustments?


  • Shawn_Mc

Posted March 26, 2002 - 11:02 AM


With out the BK mod, the accellerator pump squirt is way too much. In other words the pump spray lenght is causing a rich condition to the point where it may not foul the plug, but causes the motor to go "lazy". So the short answer is: Too rich on the pump. That is one of the ways they keep the bike from detonating with pump fuel with 12.5:1 compression. The other way is 3-D ingnition timing. Now some may argue, but this is what I understand.

  • John_Lorenz

Posted March 26, 2002 - 11:30 AM


My 00 did the same thing until I seriuosly jetted and BK moded it. I have noticed this also:: If the bike is clod or still in the in-between of full operation temp, I notice a slight bog. This is very slight now that I have it dialed, but once its warm and in heat. I will do the Emeril here "BAAAMMMM" it ignites when ya twist the grip..

[ March 26, 2002: Message edited by: EgoAhole ]

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  • dirtdad

Posted March 26, 2002 - 11:47 AM


uh...that's "BAM"! not bang. :)

  • thumper4life

Posted March 26, 2002 - 12:13 PM


what were YOU thinking?!?!? :)

  • John_Lorenz

Posted March 26, 2002 - 12:34 PM


Man I dunno to much taco bell :)

[ March 26, 2002: Message edited by: EgoAhole ]

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