What activates accelerator pump? (throttle or kick starter?)

Please settle an arguement. I say the throttle activates the accelerator pump and will flood the engine when starting. My buddy says the kick starter puts gas into the engine. My arguement is that after a fall, pull the decomp. lever and kick the engine over a few times "clears out" the engine. He says this puts more fuel into it.

The accelerator pump is activated only by the throttle. When your "clear out" the engine, pull the decomp lever in, keep the kill switch pushed in (or in my bike's case, switch it off), open the throttle all the way, and KEEP IT OPEN (don't pump the throttle-each time you do, a fresh charge of fuel is injected). This opens the slide so that as much air can pass through as possible. It is true that a little fuel will be squirted into the cylinder by the acc. pump, but you'll clear it out soon enough. A little fuel is also pulled into the cylinder when it's kicked over (through normal carburetor action), but that's compensated for by the amount of air passing through when you're clearing it out.

So, you're both right and you're both wrong.

Keep in mind that if the engine is flooded, it's not like the cylinder is full of gas, it's just that the air-fuel mixture in the cylinder is too rich to ignite. Clearing out the engine leans out the mixture enough so it can burn (and it also may help dry off a wet spark plug electrode and cool down the cylinder a bit.) This is why a hot start button is so important on these types of bikes. Why all 4-strokes aren't equipped with them is a mystery to me.

I use the hot start button when cleaning out and avoid opening the throttle.

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