2000 426 havin some issues

5 replies to this topic
  • dmoney2023

Posted June 15, 2008 - 07:06 PM


Put a new boysen cover on the bottom of my carb last year and since that haven't been able to get the jetting just right. I unscrewed the fuel screw 2.5 turns out and the popping seemed to stop and everything was just fine on my test rides.

So thinking I have it all fixed I take it out and after about 15-20 minutes of riding it starts to miss a beat now and then. Then it started to cut out on me and then completly died. I couldn't start it for a while. After I'd sit for a while it started and I could ride for a minute or two but it would die again.

My buddy says he things the fuel line is plugged or the carb is plugged so the engine isn't getting any fuel.

Any ideas????

  • Birdy426

Posted June 15, 2008 - 10:42 PM


Sounds like maybe vapor lock...is the vent line on top of your gas cap plugged or the check valve stuck closed? Also, what about the rest of the vent lines on the carb? Any of them kinked or pinched?

  • dmoney2023

Posted June 16, 2008 - 02:40 PM


Thanks for the reply. No wonder your gas tank is so full!!!

I don't think the cap is plugged, but there was gas splashing out like it was plugged or something. Like it was plugged and the pressure was actually pushing gas out of the tank rather than pulling it in. Weird.

Any other thoughts??? I'm gonna tear it apart this week.

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  • jayh300

Posted June 16, 2008 - 02:50 PM


mine did the same thing.... pushed gas out the vent. needs a new cap.
you can verify by riding it with the cap unscrewed a little, like half a turn.
mine you could actually hear the "swoooosh" when you took the cap off.
i took mine apart and saw nothing..... new cap fixed it though.

  • dmoney2023

Posted June 17, 2008 - 11:12 AM


thanks man. that is so weird. I am taking the whole thing apart, cleaning the carb, changing the air filter, oil, and i'll try a new cap too and see if it runs like a top after all that.


  • mkporn

Posted June 17, 2008 - 11:50 AM


This is also an indication of a coil that is taking a crap....Just a heads up.

I have seen 2 426 do the same thing. The first one attled my brain a bit until I compared it to a car that I worked on once. The thing would fire up cold, run great for some time then die. Couldnt get it started for a while. After letting it sit for 10 or so minutes it would fire up and run for a bit then die. I went thru the whole fuel issue and such, then it dawned on me to check spark when it dies.........Bad coil was the trouble.

Not saying that is what you have, just throwing it out there if the other doesn't seem to work.

Quick way to test the tank is to ride it til it dies, lean the bike on its side and see if you get gas thru the overflow. if not then you have a fuel issue, if you do get gas streamin g out, try starting it again, if it won't start, I would look at the plug to see if you have spark.....no spark or week spark could mean coil. If you check this, check it hot right after it dies then let it cool and check again to see if the spark comes back.

Good luck, it is probably gas but I thought I would throw this in.

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