carb troubles

9 replies to this topic
  • foxz

Posted April 15, 2009 - 10:17 PM


my buddy has a 01 426 and he used to ride it all the time and was fine...end of the season last year the bike became hard too start seemed when he got it too start the idle would hang a bit and the choke does nothing... He wanted too do a cam chain and what not so we did that while he had the bike off i gave it a real good cleaning. Now the choke still doesnt make a difference open or closed, it seemed to start really good but was really rich no matter what the fuel/air mixture screw was set at.. and now he went out on the weekend and said its really hard too start but if he gets it started it runs ok ish just rich... like rich as it burns ur eyes if ur sitting behind it.. its got a merge racing fuel screw.. stock jetting.. what could it be? thanks

  • foxz

Posted May 05, 2009 - 08:34 PM


any one??? help please!

  • boomer135

Posted May 05, 2009 - 08:50 PM


I would say first of all make sure all the variables are right, like make sure the air filter is clean and doesn't have too much oil on it and that the motor oil is all good. make sure the carb is clean. next i think the carb needle might need adjusting. it seems like you only adjusted the pilot screw and not the needle. what do you mean you did a cam chain, did you change the cam or what?

  • BC3

Posted May 05, 2009 - 08:52 PM


[COLOR="Blue"]make sure you didn't put the slide plate on Backwards.....(the straight edge goes up).....I noticed you said GOOD CLEANING...
they have a two piece slide if I'm not mistaken(can't remember) but that plate can go back together upside need a cut away to make it run right...look at the
carb parts breakdown...Or wait till gray checks this post, he knows better than me ...[/COLOR]

  • foxz

Posted May 05, 2009 - 10:26 PM


yea i double checked that lol... it started to sputter b4 i gave it a good cleaning... its rich im going to lean it a bit on the needle, but other then that i dont know why the choke does nothing?

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  • BC3

Posted May 05, 2009 - 10:39 PM


[COLOR="Blue"]There is a "Choke pick-up tube" that comes out of the float bowl on most carbs check to see that it is clean.....and fuel available in the well....[/COLOR]

  • foxz

Posted May 06, 2009 - 11:42 AM


I replaced the cam chain onthebike, ill go through itagainand I'm going too try the needle adjustment but just making sure I can cover all it all and get ridin

  • BC3

Posted May 06, 2009 - 06:12 PM


[COLOR="Blue"]Oh you did replace the chain....I wasn't sure if you did or not from what I read.....I still think you have a few carb issues but double check that your timing marks are lined up correctly since you guys did replace the chain.......I have noticed that the gas we are buying goes bad a lot sooner than I remember it used to be before all the new additives were introduced....Make sure you have fresh fuel....[/COLOR]

  • foxz

Posted May 06, 2009 - 10:41 PM


its got fresh fuel.. it runs fine when it starts.. it started second kick after chain install and it was rich so it was late called it anight and took it for a ride the next day.. he did some fuel/air mixture adj. and didnt change much but still ran like a top other then that then buddy went out next weekend and was rather hard too start, choke didnt do anything and still very rich.. like i was behind him on a hill for prolly 10 seconds idleing waiting for some one to get out of the way and my eyes were burnng.. so for that im going too adj. the needle but i was worried about thechoke issue

  • grayracer513

Posted May 07, 2009 - 05:50 AM


The choke is a simple on/off valve that opens/closes an extra fuel passage. Unscrew it and check for a reason that it may not close or seal.

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