When you push on the throttle it dies.
You need to clean the carb. 90% of the time there is a piece of crud blocking a jet.
5% of the time it's a electrical problem.
5% of the time lil passages in the carb are plugged and the carb is no good.

Take the carb bowl off, remove both jets and the float/needle/seat and clean all well.
Make sure all the lil holes are open especially in the pilot jet.
You may even have to boil the carb to open the passages up.

If it still does not run correct, jump in and tell us what it's doing. We'll help!

 

i have the same problem, i took the carb off and cleaned it as best as i knew how, but when i start my 150cc atv, if i give it a little thottle before i start it will run for about 5 seconds as long as i dont touch the thottle if i do it floods, i really am stuck, im going to take carb off again and boil with hot water but it did look clean to me. the man i brought it off told me it was because it had not been used for 8 months and now it needed cleaning. Any help would be great.
Thanks

 

double check your fuel/air mixture as well. If it is off, you will either flood it out or starve it for fuel. Just an amateurs opinion

 

Interesting percentages.

I've experienced this problem three times with 90cc ATVs from different manufacturers. All were electrical, in different spots but the same effect. There's a switched 12V wire to the CDI, and this gets interrupted somewhere. On one it was at the keyswitch itself, mine was the connector where said keyswitch plugs in, the third was at the CDI.

 

I have a weird problem.
When I start up my ATV it immediately goes full throttle but when I push the thumb throttle it dies. I just replaced the carb and throttle. When I tighten or loosen the mixture screw it wont start at all and if I use starting fluid when its like this it will only run for a few seconds then die once it uses up the fluid. Any Ideas?

 

Sounds like your new carb is faulty. Worth stripping it and cleaning out passageways and jets. Sometimes protective oil or dirt clogs a jet on a new carb. Also check you have fitted any carb breathers properly and that any gaskets between carb and manifold are sound.

 

Id really rather not have to strip and clean the carb because I don't have carb cleaner and I could return it to Amazon at no cost. Also the threads on the screws and or carb (connecting the carb and intake manifold) are stripped so I can't tighten them all that much before they pop loose again. What do you recommend I do?