Bk mod no squirt!?

7 replies to this topic
  • 426Ryder

Posted February 16, 2011 - 04:55 PM


Hey Guys,

I just finished the BK mod on my carb. I've got the bike back together and the sub frame off and there is no squirt at all. The gas is on so the bowl should be full. I completely backed out the new screw. The only thing I can think of that I messed up on is when I cleaned the carb I sprayed the diaphragm with carb cleaner. Could this be why it's not spraying? Any thoughts would be appreciated..


  • grayracer513

Posted February 16, 2011 - 05:01 PM


If you can see the pump rod operating, one of the pump check balls may be stuck open or missing. Trace the fuel circuit through the pump. There should be one on the inlet side and one on the outlet.

  • 426Ryder

Posted February 17, 2011 - 08:25 AM


Is there any way I could have ruined the diaphragm when I sprayed it with carb cleaner?

  • grayracer513

Posted February 17, 2011 - 10:03 AM



If the diaphragm were perforated, it would leak gas around the pump rod.

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  • tech24

Posted February 17, 2011 - 12:31 PM


The spring and diaphram can be put on wrong and cause this.

  • grayracer513

Posted February 17, 2011 - 03:11 PM


Do you want me not to ask how you know that?

  • 426Ryder

Posted February 17, 2011 - 05:35 PM


Sooooo the diaphragm was in upside down...:smirk: All is good there now and the pump it's squirting great. Thanks!

I did the best I could adjusting the timing and duration before it got dark and could not see. I road it around a bit and I feel like some changes in jetting are needed. At quick blips of the throttle when not moving the bike dies sometimes so I need to look into that. I also noticed that the pump spray is pretty weak after setting the duration at around .35, is this normal?

Any ideas on jetting after this mod? My specs are as followed...

Location: Phx, AZ
Elevation: 1200 ft
Temp: 70 to 110
Humidity: >10%

Main: Dynojet 165
Pilot: 45
Leak Jet: Not Sure
Fuel Screw: 3 turns out
Needle: Dynojet needle 2nd Clip

Any help would be awesome..Thanks!

  • tech24

Posted February 18, 2011 - 04:55 AM


Do you want me not to ask how you know that?

well sounds like you figured it out :smirk:

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