Last night i was at a spot just doing some slow wheelies and what not, came home and put the Z400 in the garage running fine. I take it out this afternoon after finals in a good mood to go riding and when i start it up and try to take off in 1st there is a stalling and then the power kicks in, it's probably a 2-4 second hesitation. So i turn around and head back to my house and I'm trying to figure out what's wrong with it and then it starts backfiring and shuts off idling. Any help is appreciated? Sorry about the long post.

 

I don't know if you have junk in your gas, but your idle jet could be clogged. Take apart the carb and there should be a main jet in the bowl, but there should also be a very small jet that may be up inside a tube, use a small flat head screwdriver and pull it out. Inspect it and make sure there isn't anything clogging it. This might cause all problems. Try and run the quad w/ the choke on and see if it will idle and have good throttle response. If it does, then one of the jets is clogged.

For those who care, the last carburetor I worked on was off a 2 stroke, so if a 4 stroke carb doesn't have an idle jet, let me know so I can correct myself.

 

The quickest/easiest thing you can try is check for water in the gas. Put in some good gas, put a container under the hose that comes from the carb float bowl. Loosen the screw that is on the bottom of the float bowl and let it drain until it stops. With the container still under the carb, turn the petcock to PRI and drain some more gas into the container. Tighten the screw back up and take a look at the gas and see if you see any water in it.

Tim had water in his gas once and it acted as you described.

Bill

 

Thanks guys.. i'll have to check it out tomorrow morning and post up how it goes.. thanks again for the fast replies.