426 stalling when hot

I have a 2001 yz426.  love the bike runs great.  whenever I've ridden for a while though, it begins to stall at very random times.  Usually at lower rpm's but during a race it just flat died at mid throttle as well.  It seems once it starts it doesnt go away until the bike is completely cooled off.  I just rebuilt the carb with new jets and gaskets.  Any suggestions?  Thanks in advance

Started it up tonight and now seems to be when cool or hot. It won't even rev to WFO. Really frustrating me.

Basic insulting question first: is the air filter clean? 


That out of the way, it sounds like a problem with the carb, maybe nothing more than water in the float bowl, or a piece of dirt in something.  Check the condition of the vacuum release plate on the engine side of the slide, too.  If it's cracked, or has a missing corner, that won't help.  The seal that goes between the slide and plate needs to be in one piece, too.  It will be swollen and twisted until it dries overnight, most times.  As long as it returns to its proper shape, is soft, and has no tears or missing chunks, you're OK.

The filter was cleaned before the last ride when it was acting up. I'll make sure to clean it again. Thanks for the ideas. I plan to comb over it this weekend to see what I can find. Much appreciated.

Might also want to verify that fuel flows freely to the carb and past the float needle.

will do that also.  i have new fuel lines that i can see through so i know its getting there.

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