Idling high after installing a Boyesen QuickShot – HELP

6 replies to this topic
  • jecsr

Posted March 24, 2006 - 06:23 PM


Has anyone else had this problem or am I a complete idiot :thumbsup:
I followed the instuctions and adjusted the low speed fuel screw 1/2 turn.
When I started it, it was idling fine. Put it in gear rode around the yard and when I stopped, It was idling really high. I adjusted the low speed fuel screw up and down, but nothing seems to help. Now I also need to know what the stock setting for the low speed fuel screw, if anyine knows. I can idle it down until it almost stops, then raise it up where is running right. But as soon as I twist the throttle, It starts idling high again. HELP :thumbsup:

  • 642MX

Posted March 24, 2006 - 06:56 PM


What else did you do to the carb? The quick shot has nothing to do with the idle. You have a vacuum leak or something to that effect.

  • jecsr

Posted March 24, 2006 - 07:32 PM


What else did you do to the carb? The quick shot has nothing to do with the idle. You have a vacuum leak or something to that effect.

Basically, I removed the throttle cables, decompression cable and fuel line. Loosened the clamps and rotated the top of the carburetor towards the exhaust until I could reach the bottom of the carb. I have double checked the o rings inside the cover and they match up. What could I have done to cause a vacuum leak ? :thumbsup:

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  • 642MX

Posted March 24, 2006 - 07:40 PM


Your "decompression cable" is actually your hot start. I bet its not screwed in all the way or cross threaded. Check there first. And then check your cable routing and make sure they move freely.

  • jecsr

Posted March 24, 2006 - 07:55 PM


Thanks ! I will give that a try. Do you know the factory settings on the low speed fuel screw ? I have it set at 1 1/2.

  • 642MX

Posted March 24, 2006 - 09:36 PM


I think its about 1 3/8. It really doesn't matter, as long as its more than 1 turn out and no more than 3. Just adjust the screw until it feels snappy. Good luck.

  • jecsr

Posted March 27, 2006 - 03:53 PM


Well, I took the time to remove the carburetor and made sure the hot start was installed correctly. It started and idled just fine. When I started to ride, it turned off and I couldn’t get it to start. I replaced the plug and it started up and was running great, then it stopped again. Could the low idle fuel screw be causing this to happen ? I have a Zip TY coming this week. Hopefully this will help me make the correct adjustments

Installed and adjusted the Zip TY according to the instructions and now she's running better than before.
Thanks for the Help :thumbsup:

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