4 replies to this topic
  • Jd0285

Posted May 11, 2014 - 08:10 AM


Hey guys I am at sea level and have 2006 yz450f with a 52 pilot and 170 main. Has terrible popping on decel until I get the mix screw out to about 3 1/2 - 4 turns then runs great. But the screw fell out from the vibration. So it Seems like I need a bigger pilot but a 52 is already bigger then what anyone is using on what I think is a stock bike, that I've talked to. Could anyone please tell me if this seems right or could it be something else?

  • grayracer513

Posted May 11, 2014 - 10:23 AM


At sea level, you should be running a 45/168. You either have an air leak in the exhaust system, or your current pilot jet or the pilot circuit in the carb is partly clogged.

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  • Grandy

Posted May 11, 2014 - 10:55 AM


I'm at sea level with an 06 aswell . I'm running 48/170 and I need to go to a 45 as I'm usually around one or less out on the fuel screw. You must something going on.

  • Grandy

Posted May 11, 2014 - 10:56 AM


Is your bike hard to start when warm ? Do you need to use the hot start ?

  • Jd0285

Posted May 11, 2014 - 12:54 PM


I just had the carb rebuilt and i put a 48/170 in it. It was popping really bad so that's when I put the 52 in it. I also just replaced the header pipe and the exhaust gaskets. Also it starts easy even when hot.

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