Question about BK carb mod for 426f

8 replies to this topic
  • sid_125_04

Posted August 30, 2011 - 05:29 PM


When you are adjusting the timing of the spray it says it should just barely spray the slid. the slid is just the throttle valve that moves up and down when you twist the throttle. I have the screw tapped and in just need to adjusting and want to know EXACTLY what im doing


  • Schpenxel

Posted August 31, 2011 - 06:28 AM


What is your question?

  • sid_125_04

Posted August 31, 2011 - 07:03 AM


Is the slide what im thinking it is? Im just trying to find where i should be looking for the spray when im setting it. Also since you seem to have done the BK mod does it work wonders? More snappy?

  • Schpenxel

Posted August 31, 2011 - 07:05 AM


I could tell a difference, yes.

And yes the slide is what you're thinking it is.. it's pretty obvious when you twist the throttle blade and see where the fuel squirts.

Obviously make sure you have the squirter pointed away from you when you do this.. I almost got gas in my eye last time I did one, :)

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  • sid_125_04

Posted August 31, 2011 - 07:12 AM


You do want the bike running while setting it up right? That's what i gathered from the post, or do you just have it all assembled and time it?

  • nathanpa01

Posted August 31, 2011 - 07:57 AM


You do this mod with the engine not running. The AP will squirt gas when you turn the throttle.

  • sid_125_04

Posted August 31, 2011 - 08:48 AM


Now it makes perfect sense thanks guys:bonk:

  • Schpenxel

Posted August 31, 2011 - 08:49 AM


lol..yeah, do it with the engine off. i did it with the carb off the bike actually.

  • skthom2320

Posted September 01, 2011 - 07:09 PM


I didn't feel like it did anything on the '01 bike. In fact although I had set it up to just miss the slide, it needed tuning at the track.

This bike is pretty sensitive to hot/humid weather though. I would highly recommend a couple extra pilot jets (one on either side of 42 - 40 and 45). I think I even found that the stock needle needed a clip as well depending on how hot it was.

Also, keep an extra spark plug. If that bike doesn't want to start, throw the new spark plug in and it will fire up first kick.

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