ok, i have a Mikuni 38mm carb, the factory on my blaster is a 26mm. before i decided to use my factory air box i had an open 6in filter attached to the carb. well i finally modified my air box to work with the larger carb, but now its running rich. before with the open cone i had a #350 main jet, and the e-clip set on the third notch of the needle, and it ran perfect. now with the restricted air-flow, i have a #340 with the clip set on the top notch of the needle, and it is running extremely rich. So here's my question:

1) should i go back to the open cone, put on an outerwears prefilter, and change the main jet and needle setting back

2) or should i get a smaller jet, and use the factory box

 

ok decided to go with the factory air box, i dropped down to a #280 main jet and it is running great, but the clip is on the top nitch of the needle. i was thinking about going down to a #260 for a little more adjustability in the clip. what do you guys think?

 

here is my suggestion with any carbs try it and see what happens...