Need Help Please with 2000 yz426

6 replies to this topic
  • dejavudarrell

Posted December 24, 2007 - 12:17 PM


I just bought used 2000 yz426, The guy I bought from was first owner he put low hours on bike never took it to shop, When I Bought the bike it did not start sold it to me for 1000.00.Took it to shop for tune up etc.cost me 480.00 for valve adjustment and leaking front seals and carb cleaning wheel bearings,I Pick it up from shop they started bike seem to run fine.Now today I wanted to take it out for test ride, Bike starts great but soon as you push chock off it won't run It bogs and stalls,but it will run with choke on, turn choke off when riding it won't idel and pop on deceleration runs like shit!

I bought 2 yz85 for my kids for x-mas and I want to ride with them on 12-26.CAN SOME ONE GIVE ME SOME CLUES HOW TO FIX THIS PROBLEM?
THANK YOU:mad: :banghead:

  • grayracer513

Posted December 24, 2007 - 12:59 PM


Try backing the idle mixture screw out a half turn or so.

  • 642MX

Posted December 24, 2007 - 01:23 PM


Typically when a bike will only run with the choke 'on', it has a restricted pilot jet. I see where the carb has been cleaned, but its always possible to get some dirt in the carb while re-installing it.

You can pull the pilot jet out while the carb is still on the bike. Remove the 17mm nut on the bowl and you'll find the pilot jet right beside the main jet (pilot jet is closer to the motor). Use a small flat blade and remove the jet, blow it out with some carb clean & compressed air.

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  • dejavudarrell

Posted December 24, 2007 - 02:58 PM


Thanks, I will try your suggestion.

  • atropine

Posted December 24, 2007 - 08:04 PM


Echo what grayracer said. If you are lucky, the previous owner installed an aftermarket adjustment screw that you can just turn by hand. If not, you have to put a small flat-bladed screwdriver up into the hole and turn it out.

  • Michael Cahill

Posted December 25, 2007 - 12:28 PM


Yes this sounds like a simple fix.

Just as the other guys have said, first readjust the pilot screw, and if that does'nt do it.
pull the carb out, and make sure theres not dirt plugging anything, and make sure everything is set right.

and then she should fire right up! :banghead:

  • dejavudarrell

Posted December 26, 2007 - 07:10 PM


Well I adjusted pilot screw, Filled tank with 50/50 vp gas and I notice it needed to warm up And bike runs great! Also I Installed a Iridium IX plug, bike starts on first kick 95% of the time.

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