BK Mod and Pump Timing Screw???

2 replies to this topic
  • dmxracing

Posted May 01, 2002 - 09:39 PM


Just completed the BK Mod but my "bog" problem is still not resolved. I live in Southern CA and my jetting is 168main, 42pilot, pilot screw 1.75turns out, needle in the middle. I am having a hard time adjusting the pump timing screw. I have had that damn thing in and out and I can't seem to find a good setting. How do you guys have yours set? If the screw is backed out all the way, and then you turn it til it barely hits the pump timing cam, how many turns should I have to add to the screw? Thanks...

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  • dmxracing

Posted May 02, 2002 - 07:53 PM


I think I solved the problem. When I was intially checking the pump timing screw adjustment the squirt was never hitting the slide since the idle adjustment was turned up which raises the slide. Well I backed off the idle adjustment and then the squirt would hit the slide. I turned in the screw about an 1/8 of a turn to add a small delay so the squirt would not hit the slide. It seems like it is pretty dialed in. I hope this is right...

  • John_Lorenz

Posted May 03, 2002 - 03:22 AM


Are you getting any poping on decel ?

do you have after market pipe ?

If yes to both,

also bump the pilot up to a 45

and drop the cir clip on needle one effectivly raising the needle (rich)

To fully get ride of me 00 bog after the mod I set the pilot to 45
air screw out 1 3/4
Needle up one

Have an full WB R4 exhaust.

One this was done the bike is a total blast to ride and very predictable.....................

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