00 426 popping - Fuel Screw?

2 replies to this topic
  • yzsurfer

Posted August 24, 2005 - 04:25 PM


I've read the some of the older posts. My bike is running great until I let off the gas or am going downhill and down shift to decelerate, then it starts popping in the most annoying way.

About a year ago, I had Motoman393's quick adjust fuel screw fall out on a ride. The bike popped (similar to the way it does now) but wouldn't run unless I gassed it. I stopped and found the fuel screw hanging on my footpeg. Put it back in and went on my way. This got me thinking, so I pulled out the Zip-Ty quick adjust one that I put in later (just because of the bling factor) and found the rubber O-ring was missing. I'm guessing this is the problem, somehow air is getting by and creating the problem. Sound like I'm sniffing up the right tree?

The bike has a Hayabusa sparkplug cap that has the coil in it (stock coil removed).

Any thoughts, anyone?

Thanks, Jeff

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  • bg10459

Posted August 24, 2005 - 04:44 PM


The O ring could still be in the carb. You might be able to fish it out with the fuel screw. If not, that could definitely be the problem, but where did it go? :D :D
When did the problem start?

  • yzsurfer

Posted August 24, 2005 - 08:42 PM


That's a good question! I don't remember NOT putting it on. Bike ran great for awhile (like a year). I did take out the new fuel screw and looked in the hole where it goes using a flashlight and saw nothing in there.

Forgot to mention that it has an 02 needle (thanks to Hick), BK mod, and power now mod. I've never changed the accelerator pump diaphram.

I think for now, I'll pull the carb and go through it. It could probably use it regardless,

Thanks, Jeff

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