Yz490 blaster flooding issue

Recently finished up a project YZ490 conversion on a Yamaha blaster frame and I’m having a very peculiar issue. Thing does NOT like to start, I’m talking if it’s cold you have to pop stsrt it for the better half of 20 minutes. Issue being that the carb is dumping fuel into manifold whenever I shut the thing off. Once it’s running, it runs like crazy. Once it’s hot, if you keep it wide open it normally starts on the second kick, If you don’t let it sit for more than a minute. I have tried two different carbs entirely and all sorts of jets, needle positions, float height, etc... cannot figure out what’s going on. Thinking the only common thing between the two carbs is the angle of the carb, it sits slightly titled back (toward the motor) but I’m grasping at straws.. any ideas??
 
I'm asking a really obvious question here but are the float needle and seat in working condition and sealing? If you take the carb off of the machine, rig up a jug of fuel above the carb with gravity fuel feed and hold the carb level then angle it like it sits in the machine, does float valve leak?
 
I'm asking a really obvious question here but are the float needle and seat in working condition and sealing? If you take the carb off of the machine, rig up a jug of fuel above the carb with gravity fuel feed and hold the carb level then angle it like it sits in the machine, does float valve leak?
I will give it a try
I’d hope they are sealing, they’re brand new from mikuni..
I’ll let you know
 
I'm asking a really obvious question here but are the float needle and seat in working condition and sealing? If you take the carb off of the machine, rig up a jug of fuel above the carb with gravity fuel feed and hold the carb level then angle it like it sits in the machine, does float valve leak?
Tested needle seal and it’s good, bent the float needle arm even more and rigged the carb so it sits flatter. Went from a 35 pilot to a 30, will give it a shot once the pipe is back on
 

yamanube

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Floats aren't cracked and filling with fuel? Is the fuel turned off when its sitting?
 
Floats aren't cracked and filling with fuel? Is the fuel turned off when its sitting?
Ended up being that the case was full of fuel and the crank seals were really shot.. changed the seals and got her to idle for a little bit and it cleared up. Also ran the reed block over a piece of sandpaper on a block of wood, the old rubber coating yamaha put on the ends was chipped up bad and killing the seal. Starts up easy now, it will be going up for sale soon.. thinking it makes about 60-65 at the crank in a blaster frame!! Sadly it only temporarily filled the standup void in my heart lol
 
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