Carb spittin out fuel when using throttle

You have a plugged up Carb. Probably from lack of use or seasonal storage. Always run your fuel dry whenever there is a possible lengthy amount of storage time. Run until the engine dies so that there is no chance of the fuel turning sour and fouling out your carburetor due to storage and hindering the next start up.
Always Check the basics first. Make sure you have Spark, Fresh Fuel and Compression. Once completed, assuming you have the essentials, remove carb, use eye protection, spray carb cleaner in every hole, jet, inlet and outlet while opening / closing throttle then immediately follow with compressed air to push through foreign material.
Reassemble
Some people say to soak carb over night in cleaner then use compressed air-- Sometimes we just don't have time to do all that.

What I do is take the carb off being careful not to break any gaskets, take it completely apart soak it in carb cleaner blow the parts dry and reassemble. replace the fuel tank filter, plug if fouled, and readjust the HI & LO speed jets. Works for me several times, leaving fuel in the tank and carb it gums up, run the carb dry before storing.

The only thing that I can guess is happening is the engine is spitting back while you're trying to start the engine. This ignites any gasoline that is in the carb or throttle body and the flame is burning you air filter. The thing to do is to continue to turn the engine. This sucks the flame into the engine. It won't hurt anything because after all, you are trying to start a fire in the engine.

If your bike equipped with a carb, pull the enricher out, milk the throttle about twice, turn the ignition switch on, and then push the start button while leaving the throttle completely closed. This is very important, leave the throttle closed. This is how an enricher circuit works. If you crack the throttle open even the slightest bit, the air is drawn through the carb instead of the enricher circuit and this causes the spit back in the carb. It will do the same thing with fuel injection. Start the bike with the throttle completely closed. It should fire and go to a high idle with the enricher out or with a fuel injected engine.

Good Luck
Steve

Your description sounds like fuel restriction in the main circuit. Sometimes you need to soak the carb in carb cleaner and then blow out passageways with compressed air.

There is one "cheat" but it involves some higher throttle, and that is you remove the air filter, rev up the unit and briefly place palm over the intake. Sometimes this is enough to pull the obstruction free.

Check the fuel filter, air cleaner and muffler for plugging. Was the carburetor disassembled when soaked and did you use compressed air to blow out all passages? If the carburetor jet screws have been moved, preset them as follows: Turn both H and L screws CW to stops (lightly), then back out CCW each screw 1-1/2 turns. Start the engine and allow to warm up. Pull the throttle full on and adjust H CW until the engine speeds up somewhat but 4-stroking. Proper adjustment is when the engine 4-strokes, but immediately 2-strokes when cutting. Allow to idle and adjust L CW until the engine runs fairly well, but still allows the engine to 'follow the throttle'. Adjust idle speed screw so that chain stops turning, but the engine continues to run. Hope this helps!

The idle circuit is still plugged up or it would not be giving you this problem. Remove the carb and dis-assemble it then soak the parts in denatured alcohol for 30 minutes. Then use a spray carb cleaner to finish the job. Spray into all the little holes in the carb body. Especially spray into the air screw and throttle screw holes. Reassemble the carb and LIGHTLY seat the air and throttle screws then turn each of them one and one half turns outward. This is the factory setting. Before putting the slide back into the top of the carb, move the clip on the jet needle one notch lower on the needle. This will richen the low end fuel mix. Install a new spark plug and clean the air filter. Please rate my answer. Thanks.

Two things will freeze a throttle >> a rusted cable and a stuck slide. The usual problem is a stuck slide. Disconnect the air cleaner and unbolt the carb. Pull it to one side and immerse it and the cable end in a small coffee can filled half full of denatured alcohol. Let it soak for 15 minutes. Now set the can aside. File down the end of an old toothbrush and put the new chisel end into the inlet side of the carb and under the bottom edge of the slide. Tap the end of the brush with a plastic hammer to pry the slide upward and break the slide free. The carb is going to need a through cleaning so remove the float bowl, air and throttle screws and slide assembly and let the parts soak in the alcohol along with the carb body. An hour soaking should be good. Now clean with spray carb cleaner, concentrating on the screw adjuster holes and drill circuits in the body of the carb. After reassembly, LIGHTLY seat the air and throttle screws then open up one half turns outward.

Drain the gas tank and clean it out. remove the petcock and clean it also. Install an inline fuel filter. Please rate my answer. Thanks!

you shouldnt have to resync the carbs as long as you dont touch the mixture screws or the screws for the throttle blades. you wont have to pull the jets completly out to clean them just spray the heck out of all the orifaces with carb cleaner once you have them pulled apart. Also whe you put it back together make shure the carb seal to the engine and airbox are tight with no leaks, this will make it run bad also

Sounds like a fuel or intake problem to me, start the bike and spray brake cleaner onto the intake where it goes into the head, if the bike stumbles then you have an intake leak and have to change the seals or just tighten up the intake manifold. Another thing you could do is remove the carb (if it is carburated) remove the float bowl and clean everything including the jets, you could have some **** in there that is plugging things up. Also try removing the air cleaner and spraying a can of carb cleaner into and around the carb. Also try removing the gas tank and completely cleaning it and the petcock screen out, you could have something in the gas tank that is migrating to the petcock and causing a blockage.

1st-take off fairings & tank,seat, take carbs off. drain fuel, & turn over on bench. take bowls off.disassemble jets & floats in each carb, do not mix components from each carb.soak in carb cleaner until clean, & no obstructions in jets. soak bowls also.squirt through carb. air & fuel circuits w/ spray carb. cleaner.when everything is cleaned, reassemble carbs. check carb. float needles for leaks. if all ok ,install carbs on bike.now using remote fuel supply bottle, hook up to carb set.start bike & warm it up,now synchronize carb. set w/ vacuum guage set.reassemble tank,seat, and fairings. note:this really is not a job for the novice w/o competent supervision, a service manual is recommended before beginning.