01 426 starting hard and running bad?

4 replies to this topic
  • 01426

Posted December 14, 2008 - 03:29 PM


I have a 01 426, I have had it for about a year now. When I got it, it would start first kick every time (after I mastered it) and run great. Now I have to kick it about 10-15 times to get it to run I also have to twist the throttle about 5-8 times every time I kick it just to get it to fire. I have put a new plug in it and the carb was cleaned about 5-months ago. I have only ridden it about 2 good times since the carb was gone through, although I do take it to a field near my house about every 2-3 weeks and run it until it gets up to temp. I also keep good gas in it and if it sets with any gas older than 2 weeks or so I will top it of with fresh gas. When I get it to stay running and I take it for a ride it wants to backfire and just isn’t running up to par, it sputters bad unless you are getting on it hard.

What should I look into first?

  • William1

Posted December 14, 2008 - 04:25 PM


Check the valve clearances

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  • motojoe_23

Posted December 14, 2008 - 04:55 PM


Check your valve clearance first. Also check to see that it is getting fuel from the petcock properly. Then re-check the jetting and carb adjustments. It sounds lean to me.

  • craigdieselmac

Posted December 15, 2008 - 06:06 AM


This is exactly what I just went through.. If you happen to have a syringe, not one with a needle, one like you would measure medicine for a child with, take your airfilter off and squirt about 1/2 teaspoon of gas in there. It doesn't seem to matter what angle you squirt it in at. Jump on the bike and kick it over a couple of times. If it starts and runs fine, then dies, you most likely have a carb problem and are getting leaned way out. If you don't have a syringe and arent scared of ether (I'm not, but some people are), squirt ether in there and see if it starts.

If it is a lean condition, it could be several things, most likely a clogged pilot jet, which is easy enough to fix. Take the bowl out, take the jet out, blow through it, then look to see if it is obstructed. Run some .032 safety wire or equivelent through it just to make sure it is clean. Check your main jet while you are in there, although I doubt it will be clogged.

This is just the first in several troubleshooting steps.. let me know if I can help any further... you could also try the fuel forum on here, I can't remember the guys name on there, but he seems to know a lot about these things..

  • 01426

Posted December 15, 2008 - 06:23 AM


In checking the valve clearance you mean the valve lash right? I will also take the cab back off and go through it again along with the fuel system and see if this gets me going again.

Thanks for the help.

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