426 Hard to start after sitting for 9 weeks

6 replies to this topic
  • 78sharpshooter

Posted August 12, 2006 - 05:00 PM


After breaking my ankle badly my bike has sat (with fuel in the carb) for over 2 months. It seems to start slightly better if I drain the bowl and then refill quickly and kick it a couple of times. I just checked the valve clearances and they are right on and replaced the cam chain (painful) and started it up and it runs great. I know I should clean the carb but is there anything specifically that I should do?

  • PK

Posted August 12, 2006 - 05:19 PM


With a broken ankle you probably weren't to worried about it at the time, but did you drain the float bowl or was it full of gas the whole time? Mainly you need to clean out the passage ways for the fuel and air. Pull the jets out and use compressed and carb cleaner to clean them all out. I would try pull starting the bike (I would have said push start it, but with a jacked up ankle how fast can you push?). I've seen where once it fires up, your fine and it will resume it's prior starting traits.

  • missionary

Posted August 23, 2006 - 04:48 PM


My sugestion is remove the float bowl and spray carb cleaner in the bowl and uderside of the carb. Be sure to spray up the main jet. This will clean all the old bad gas out. Then put some fresh gas in and start it up. If possible run some VP fuel/gas through it. That will clean it out.

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  • 642MX

Posted August 23, 2006 - 05:28 PM


Pull the carb, get your book out and start cleaning it. If you forget where something goes then you can reference the manual.

  • mpl239

Posted August 23, 2006 - 05:42 PM


Make sure the hole in the slide plate is DOWN!! this minor error will cause major headaches

  • motokid338

Posted August 23, 2006 - 05:45 PM


I just cleaned out my float bowl on my 450f becuse it was really hard starting but now it but now it starts first kick :thumbsup:

  • Vetmxrider

Posted August 23, 2006 - 06:38 PM


One time when my YZ426 sat for several weeks it would only run with the choke on due to the pilot jet becoming clogged with varnish. Just remove your pilot and main jets and spray them with carb cleaner. If you have access to compressed air, use it to blow out the jets after after spraying them with the carb cleaner. I hope this helps.

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