Just purchased a 99 YZ400, Realizing that my OEM carb is not letting my bike idling and preparing to do the carb conversion

1 reply to this topic
  • Parker856

Posted September 07, 2016 - 06:23 PM


So i looked at just about every post i could find on here about the conversion, and i know they are pretty much plug and go besides stretching the boot a little. If i remember correctly the 02-09 will work, but the 05+ are slightly better.. it is very slim pickings right now from what i can find of the YZ450f carbs, none of them have any of the cables included and are $200+.. i just replaced the intake and exhaust cam with the HotCams for the auto decompression so i have that lever for the hot start, just need the cables and carb...my buddy said the honda carbs are exactly the same(thats what his dealer said) and i just wanted to know if i could include Honda carbs in my search.. thanks!!



sat for a winter, got it for $600.

had a local shop go through it and rebuilt the carb and cleaned it ultrasonically and just no good. After lengthy troubleshooting, cleaning the carbs again, checking valves again, they threw a carb they had on it and it fires right up and runs great.

(have a post in the classifieds) 


THANKS FOR ALL THE INFO GRAYRACER513, havent met you yet but i already respect you for the time you put in to help strangers!


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  • grayracer513

Posted September 08, 2016 - 06:30 AM


Well, your buddy is wrong.  The carb on a CRF450R is a 41mm bore, while the YZ450 is 39mm.  The Honda carb might work, or you might spend a lot of time re-working the jetting.

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