Another BK Mod Question

5 replies to this topic
  • Thumpin_426

Posted September 13, 2001 - 10:56 AM


When looking down the throat of the carb to check the spray duration and slide, I am assuming the bike is running with the subframe and the muffler off, correct?

If so, this wont screw up the valves like a car running without it's exhaust will it?

Second, when BK says to stab the throttle he is refering to a quick full throttle twist, right? My spray only seems to last approximately 1 second! Everyone else I have talked to said their's lasted 3-4 seconds???? Am I doing something wrong?

  • forloop

Posted September 13, 2001 - 12:47 PM


No, you don't need the bike running. You want to check it with the bike off. For one, if it back fired you could get burned.

I took my carb off and testing it on the bench. But, you can do it on the bike with the motor off.

I would take the plug out to help the gas excape.

01 YZ426F #85 Vet C

  • Thumpin_426

Posted September 13, 2001 - 01:13 PM


So when you look down the carb with the bike off and give it full throttle, watch the spray from the time you gave it full throttle until the spray stops, (still at full throttle) correct? Is this the spray duration that should only be .3 seconds?

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  • motoman393

Posted September 13, 2001 - 02:02 PM


Correct! Right as you twist the throttle click the stopwatch (while keeping the throttle wide open) and click the stopwatch when the stream stops! and that should be ~.3secs. The bike SHOULD NOT be running while doing the mod. I took my carb off the bike and tested the duration on my workbench/garage floor!


I get my kicks on a 426!
Motoman393's MX Site

  • Thumpin_426

Posted September 13, 2001 - 02:25 PM


Thanks for the input!! I'm on my way now. I'll let you know how it turns out.


  • jaybird67k

Posted September 13, 2001 - 02:48 PM


The bike will not run with the back half of the exhaust off, I tried just for grins and giggles shortly after I got the bike just to hear it that way, but it will only fire not run.

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