jordanscycles Posted August 2, 2009 Share Posted August 2, 2009 my xs 400 with 4k miles is fouling plugs almost as soon as I put a new one in. I think the last new ones lasted 20 miles. I went through the carbs already 5 times. Last time I put in new stock size jets. I have turned the air screws out to where they are almost coming out. should i get leaner jets? Link to comment Share on other sites More sharing options...
TylerP Posted August 2, 2009 Share Posted August 2, 2009 Are there any restrictions in the air intake? Could the fuel level be to high? If it has brass floats make sure they do float. Air mixture screws? Are you sure they do not control fuel? If the screw is on the engine side of the slide it controls fuel and they will be open way to far. 2-3 turns out from bottomed should be close. Link to comment Share on other sites More sharing options...
jordanscycles Posted August 2, 2009 Author Share Posted August 2, 2009 Are there any restrictions in the air intake? Could the fuel level be to high? If it has brass floats make sure they do float. Air mixture screws? Are you sure they do not control fuel? If the screw is on the engine side of the slide it controls fuel and they will be open way to far. 2-3 turns out from bottomed should be close. Yeah the screws are on top of the carbs right against the engine. I'll do that... After getting another set of bloody plugs tomorrow. Thanks for the help I'd have never figured that out before I sold it out of frusteration. Also as far as air restriction I think it's fine because the air filters tubes and everything look great. Link to comment Share on other sites More sharing options...
jordanscycles Posted August 3, 2009 Author Share Posted August 3, 2009 i just swapped out the carbs with ones i got from ebay, which dont have adjusting screws and have fixed mixtures. Works perfectly, i'll keep the old carbs for parts. Link to comment Share on other sites More sharing options...
Moderator drewpy Posted August 4, 2009 Moderator Share Posted August 4, 2009 i just swapped out the carbs with ones i got from ebay, which dont have adjusting screws and have fixed mixtures. Works perfectly, i'll keep the old carbs for parts. they are not fixed just mechanically hidden Link to comment Share on other sites More sharing options...
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