Fresh Rebuild: Dies when applying throttle

I tried to start up my 06 yz450f today after a full bottom and top end rebuild. The bike fired up( and continues to do so each time I start it) quickly and idles fine.

Problem is it dies EVERY TIME i apply even the smallest amount of throttle. IF I just very slowly twist it, I can hear it start to slow down and it will die even before an 1/8 of throttle has been applied.

The carb was drained before I began the rebuild, so I think I can rule out clogged jets??

Also, it doesnt seem very responsive to the idle adjustment screw.

What would cause this? Its boggling my mind at this point:bonk:

have you connected the carb properly you may have an air leak

The carb was drained before I began the rebuild, so I think I can rule out clogged jets??

Not by the sound of things, no.
have you connected the carb properly you may have an air leak

What he said.

Check your airbox boot seal to the rear of the carb.

What he said.

Check your airbox boot seal to the rear of the carb.

I did have one hell of a time getting the seal on the back of the carb... would even a small air leak cause this to happen??? It just seems like the bike may run a little strange, but it wont run at all as soon as I being to apply throttle...

are you sure you got the timeing right long shot but check the tps make sure its hooked up and has not been moved

I did have one hell of a time getting the seal on the back of the carb... would even a small air leak cause this to happen??? It just seems like the bike may run a little strange, but it wont run at all as soon as I being to apply throttle...

After I replaced the subframe/airbox boot it wouldn't take throttle at all and idled poorly, to the point I kept increasing the idle speed to try to get it to accept throttle without the choke on. While the bike was idling, I finally reached down and grabbed the side of the airbox boot and gave it a strong tug/wiggle and the idle instantly climbed and it would rev normally. I turned the idle back down to normal and it ran perfect.

thanks for the info...sounds exactly like my problems.

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