please help. 06yz450f

4 replies to this topic
  • ProjectDIRT

Posted May 14, 2008 - 06:09 PM


well finally after the defective cam from hot cams i got my bike back together. the cam gear slipped on the camshaft i guess it happens sometimes since the gears are just pressed on. but i have a cp 13.75 race piston and stage 1 hot cams im trying out a 180 main and and the needle is at 3 now and have the fuel screw at 2 1/2 out itll start sometimes but wont stay running unless im giving it like 1/4 turn of gas some shed light on this and help me get it tuned lol. thanks oh and it has pro circuit ti header and fmf ti factory 4.1 with a kn filter.using c12 oh and kicked on me and damn did that hurt my knee.

  • KJ790

Posted May 14, 2008 - 06:32 PM


Could be a lot of things. Does it run alright if you rev it up or does it still run like crap. If this is the case then your timing could be off by one tooth on the intake cam (a common mistake if timing was set with the tensioner out). Also make sure your hot start isn't stuck on or pulled out at the carb (can easily be dislodged while working on the head).

If it runs fine at higher RPMs then most likely your pilot circuit is off. I would need more information on what it is doing to figure out if it is lean or rich. Have you tried playing with your fuel screw to see if anything changes?

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  • ProjectDIRT

Posted May 14, 2008 - 06:48 PM


yea. well its at clip 4 it was at 3 before all this. and the timing is 100% correct. i work on cars just efi though. not the best at carbs. but i know some of you are wizards with them thats why i have turned to you guys once again. i can tune with a laptop lol. and i think its lean was thinking of going up on the pilot or just using the screww alittle more. but how many turns out should the idle speed be at?? my idiot buddy turned it to be a ashdhasj. like atleast 3 turns.

  • grayracer513

Posted May 14, 2008 - 08:13 PM


If you had the slide out, check the position of the slide plate, #10 below. Note that the square edge with the hole goes down, even though it would appear it should be the opposite. This is probably the single most common mistake made with these carbs.

Posted Image

  • ProjectDIRT

Posted May 14, 2008 - 08:19 PM


ok. but i never took the slide out all i did in the carb was change jets. but thanks for your input. im pretty sure that its in the pilot circuit and the idle speed. because when i get it fired up i can hold the throttle to keep it running. i havent got it higher than 3000. i have a 48 pilot should i try the 52 that i have?? i really wish my bud wouldnt have messed with the nob

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