450r Carb Acting Odd

[minimac21234]

Ok, so here's the deal. I have a 2001 400ex. Here is what's happening with the carburetor and what I know thus far.

-Started and ran a few months ago but it took forever to get it running aka it only ran when it was warm. It would "hiccup" when it was cold but when it warmed up it ran ok. Figured it probably needed to be cleaned and rebuilt with new orings.
-Rebuilt carburetor not onces, twice, or 3 times but 4 effing times. That made it worse. Now it wont run.
-To get it to run for a second i have to snap the throttle a few times to get it going. Then it "hiccups" and sprays a mist of fuel randomly from the intake of the carburetor(where the airbox/filter is attached to)
-Exhaust backfires.
-Put a buddy of mines carburetor on my quad and it runs perfect. No hiccup, no hastle, no hesitation. Its also a 450r carb from the same era and it is jetted the exact same way as mine.
-All jets and passage ways were completely removed, cleaned with carb and choke cleaner 3 times, submerged in carb cleaner for 2 days, and shot compressed air through every passage way.

Reaaaaddddyyyyyyyyy. Go! Lol I hope you guys have some good ideas. Me and 4 of my friends couldnt figure this out. Thanks in advance.

-Mike

[DnB_racing]

which 450 carb do you have? the 04/05 or the +06 with or without hot start? there are three different styles and the + 08 have slightly different slides and needles then some of the 06/07, which do you have? im assuming you have the 04/05, but it still will be helpful to know,, but from the sound of it spraying into intake instead of towards motor, the either something is bent or its still dirty

did you rebuild your accelerator pump diaphragm?

[minimac21234]

It is an 04-05. I didn't rebuild the accelerator pump diaphram but it looks to me that it is functioning properly. Sprays fuel into the motor.

It's not that it's spraying out. It's hard to explain. When the carb is doing the "Hiccup" thing, it shoots out a mist of fuel. Enough to make my frame moist with fuel in the space right behind it. It won't run at all when I go to crank it over. If I snap the throttle a few times, then go to crank it over, it will run for a second, "hiccup", spray a mist of fuel, and die.

[DnB_racing]

Originally posted by minimac21234
It is an 04-05. I didn't rebuild the accelerator pump diaphram but it looks to me that it is functioning properly. Sprays fuel into the motor.

It's not that it's spraying out. It's hard to explain. When the carb is doing the "Hiccup" thing, it shoots out a mist of fuel. Enough to make my frame moist with fuel in the space right behind it. It won't run at all when I go to crank it over. If I snap the throttle a few times, then go to crank it over, it will run for a second, "hiccup", spray a mist of fuel, and die. I know you said it runs fine with another carb, but that sure does sound like valves or timing

[minimac21234]

Ya i'm 100% sure its the carb. I tried my buddies carb on 2 seperate occasions just to double check that it wasnt timing. Even with the good carb on it running good, i checked timing afterwards. Its spot on. I just bought a new one off of ebay. Ill sell the old one here as parts for someone. I just want to ****ing ride! Thanks for your help.

[airmobile101]

Sounds like a AP issue, its suppose to shoot a stream of fuel, not a mist.