more jetting thoughts from someone less intelligent.

[dank]

ok, i love the way m bike runs down low, but once i get say 1/2 throttle, its like the rpms stop and hover. i dont notice this so much riding, other than it just seems to run flat, at which point i shift, but that happens right around 1/2 throttle. its gets flat and kindof sputtery, i dont know exactly how to describe it. so im wondering where to start. i have a 40 or 42 pilot, i cannot remember which right off hand, but the way i understand it the pilot only really comes into play at the lower end of the rpms, i also have a 178 main jet, and i have no clue what needle i have. i tried to take out the retaining screw on top of it, but i could not find the correct size (i think its supposed to be a 6, but i think a previous owner tried to use SAE tools and stripped it out. the size is somewhere between 5.5 and 6mm, but neither work.) so im wondering if i should take a vice grip to the screw and try moving the needle and replacing the screw, or if i should try a different main? i dont know if its running to rich or too lean on top, but i think it would be safer to move it richer first and see what happens before i go leaner. any suggestions would be great!