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Ariel Red Hunter · 06-22-2019, 05:59 PM

I am amazed at how many new riders of Chinese bikes start chasing too lean issues by going immediatly to the main jet. thinking it will be THE ANSWER. Then they have trouble with starting, or mid-range issues. They are trying tuning these carburetors the same as a Carter AFB, or a Holley. They are not the same - they are so different one might as well have been designed on Mars while the other comes from Pluto. The sooner you put that Holley away in a little box in your miind, and think of these carbs as something new and different, the sooner you will find success. Here's the short, no frills way I've tuned these type carbs for more than 50 years. It's quick and easy. First thing is un-plug the idle mixture screw,screw it gently in until it just bottoms out. Then set the idle mixture screw at 1 1/2 turns out. Now,change pilot jets bigger and bigger until you have a very strong 1250-1450 idle. If you are too rich, you will see a little black smoke in the exhaust. Try to correct it by leaning out the idle mixture screw. If you have to go beyond 1 1/4 turns in order to stop the smokeing, change your pilot jet 1 step leaner. Once you have your pilot jet mixture right, the rest is easy. I don't go any leaner with the pilot jet then absolute necessity, as a rich pilot jet helps low end punch out of all recognition. Next, make sure the needle clip is in the middle slot on the needle. Now, find a 55 mph road, make sure the engine is warmed up , and run for a half mile or so at 50 mph, then pin it wide open. When it has settled in to pulling hard, back the throttle off 1/8th turn. One of three things will happen. If you get a momentary surge of power, main jet is too lean. If the engine acts soggy, or wooly, main jet is too rich.If neither of these things happen then your main jet is very close to spot on. THER IS ONE THING YOU WILL HAVE TO REMEMBER; THE PILOT JET AFFECTS FUEL MIXTURE FROM IDLE ALL THE WAY UP TO THE LAST GASP...ARH

for your attention and patience.

06-22-2019, 05:59 PM	#1086
Ariel Red Hunter Join Date: Jun 2016 Location: akwesasne, NY-13655 Posts: 2,220	Pilot jets. I am amazed at how many new riders of Chinese bikes start chasing too lean issues by going immediatly to the main jet. thinking it will be THE ANSWER. Then they have trouble with starting, or mid-range issues. They are trying tuning these carburetors the same as a Carter AFB, or a Holley. They are not the same - they are so different one might as well have been designed on Mars while the other comes from Pluto. The sooner you put that Holley away in a little box in your miind, and think of these carbs as something new and different, the sooner you will find success. Here's the short, no frills way I've tuned these type carbs for more than 50 years. It's quick and easy. First thing is un-plug the idle mixture screw,screw it gently in until it just bottoms out. Then set the idle mixture screw at 1 1/2 turns out. Now,change pilot jets bigger and bigger until you have a very strong 1250-1450 idle. If you are too rich, you will see a little black smoke in the exhaust. Try to correct it by leaning out the idle mixture screw. If you have to go beyond 1 1/4 turns in order to stop the smokeing, change your pilot jet 1 step leaner. Once you have your pilot jet mixture right, the rest is easy. I don't go any leaner with the pilot jet then absolute necessity, as a rich pilot jet helps low end punch out of all recognition. Next, make sure the needle clip is in the middle slot on the needle. Now, find a 55 mph road, make sure the engine is warmed up , and run for a half mile or so at 50 mph, then pin it wide open. When it has settled in to pulling hard, back the throttle off 1/8th turn. One of three things will happen. If you get a momentary surge of power, main jet is too lean. If the engine acts soggy, or wooly, main jet is too rich.If neither of these things happen then your main jet is very close to spot on. THER IS ONE THING YOU WILL HAVE TO REMEMBER; THE PILOT JET AFFECTS FUEL MIXTURE FROM IDLE ALL THE WAY UP TO THE LAST GASP...ARH for your attention and patience.
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