300ex carb question

[dabkrk45]

i have a 300ex with white brothers e-series exhaust. my question is when im riding whenever i try to full throttle it, it sputers when im at higher rpms, does this mean im to lean or rich, or does it mean something else? what does the pilot jet actually do?

[cals400ex]

what are your mods and what size jetting did you go with?

[dabkrk45]

white brothers e-series , K&n with air lid off, and i have a mikuni flatside carb, the main jet is 150, and i know that sounds high but thats waht it came with when i bought the carb brand new. i raised the needle clip up one and i dont know what the pilot jet is b/c i didnt change it.
Does mikuni carbs have bigger numbers for their jets?

[cals400ex]

make sure you tell everyone your using a mikuni. i haven't talked to anyone who used those on hondas. i have no clue on what jet to tell you to use because of the carb your running. i would run it at full throttle, pull in the clutch, shut the bike off at full speed, come to a stop and check the color of the plug. this should give you an indication if your rich or lean. if the plug is black, your rich. if it is whitish, your lean.

yes, you can get mikuni jets of any size.

[beak7707]

My friend is running the mikuni flat slide and I think he has a 150 or 160 main. One thing though that carb is a b!tch to jet, we have had all kinds of trouble with his carb. All the pilot jet does is control idle to 1/4 throttle. So if it idles fine then you pilot is good to go. I would say its your main, sounds like you might need to go up one size which will be a 160.

[dabkrk45]

OK Thanks i will have to try that today

[dabkrk45]

i put a 155 main, a 12.5 pilot jet and put the clip on the center of the needle and it runs really good now
Thanks for your help