Carb adjustment screw

Hicksi

New member
Hey,

I've just cleaned the carb on my 2001 EC300, Keihin model.

Theres an adjustment screw on the LHS with a spring tensioner, is this the air adjustment screw? And how many turns out should it be stock? So i have somewhere to go from without it revving its nuts off when i start it... :rolleyes:

Thanks
 
Hey,

I've just cleaned the carb on my 2001 EC300, Keihin model.

Theres an adjustment screw on the LHS with a spring tensioner, is this the air adjustment screw? And how many turns out should it be stock? So i have somewhere to go from without it revving its nuts off when i start it... :rolleyes:

Thanks

That tiny little brass screw, back near the inlet flange, is an air screw. It works in conjunction with the pilot circuit to give closed to near closed carburetion.

There is another screw on the LHS of the carb that is right in the middle of the body and angled upward slightly. This adjusts your slide position when the throttle is closed - if its set too high / too far in the tendency of your bike will be to rev like crazy and not settle into a good idle.
 
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Sweet,

I hadn't had any issues with the little brass screw (air screw), as the engine was running ok before i took it appart. It was suffering from a high idle though, which i now presume to be the result of this screw (one in the middle of carb body).

How many turns should this be out? I've put it at 3 1/2? Dont want it screaming at me when i try and start it.

Thanks
 
Sweet,

I hadn't had any issues with the little brass screw (air screw), as the engine was running ok before i took it appart. It was suffering from a high idle though, which i now presume to be the result of this screw (one in the middle of carb body).

How many turns should this be out? I've put it at 3 1/2? Dont want it screaming at me when i try and start it.

Thanks

Back it out a couple more turns, then start the bike and warm it up using the throttle to keep it running. Release the throttle and see where the bike idles. If the engine slows down and dies, turn it in a little bit at a time until you've got it where you want. If its still racing, turn it out some more.

Some guys run high idle to prevent stalling in corners - set it where you like it :D
 
hichsi,once you have your idle set, go to the small air screw adjustment on the back left of your carb. adjust it so you get a quick fast smooth snappy reaction when you blip the throttle. this usually is where the bike idles at it's fastest rpm as well.once you get this set,you may want to reduce your idle speed,as your probably running higher idle than you were before. stop the bike, turn/count the turns in to lightly bottom the air screw.ideally you should be between 1.5 and about 3 turns out from seated. if your over or under this area,you should go up or down on your pilot jet by a size. then repeat the process and reset the air screw to the new pilot jet.
 
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