I have a 1999 Yamaha Warrior and I just replaced the carburetor with a brand new one and I also replaced the intake boot. It was running before the new carb. and intake boot but was running a little rough and the previous carb. was missing the cover so I just figured it would be better to replace the whole carb. with a new one. I've adjusted the fuel mixer screw and the idle screw. It won't start and idle but I can use the throttle to keep it running. Any ideas?

 

Clean the jets out, yes it is new, but could have dirt or metal shavings left in from manufacture. Set the mixture screw about 2 turns out, and see if you can get it to idle then.