what is an accelerator pump?

[Rider-trx_250ex]

Alright I hear of accelrator pumps all the time on carbs but what are they?

[rooster300ex]

Its a lil pump on the side of the carb that pumps alil raw fuel into the carb when your on the throttle. I bet somebody can explain it alil better.

[jsmith2232]

the accelerator pump works to help the flow of gas under sudden bursts of the throttle. if you take your carb off with the gas hooked up and slowly pull the throttle nothing will squirt out of the carb but if you smack the throttle it will shoot a stream of fuel out of it.

[itismejoshy]

if your bored and have the airbox off you can see the pump in action just turn off choke and look in the intake side of the carb, then hit the throttle, you'll see a stream of gas shoot into the carb

[bwamos]

Originally posted by itismejoshy
if your bored and have the airbox off you can see the pump in action just turn off choke and look in the intake side of the carb, then hit the throttle, you'll see a stream of gas shoot into the carb

Just don't look in the engine side of the carb.. unless you like gasoline in the eye.

Whay an accelerator pump does is when you hit the gas quickly the slide open sup on the carb.. but there is a short period where the suction hasn't yet built up to draw enough gas in the carb through the main jet causing a temporary lean condition. This will cause a hesitation. The accelerator pump squirts a small amount of fuel into the engine intake to help counter this lag/hesitation.