jetting

[riderofthestorm]

hey guys! i just changed my main jets from a 240 to 280, as i was told to, cause of my mods, dg pipes, kn in box with drilled lid, it ran good with the 240s and the needle set on the 4th clip on the rich side, 27.5 pilot air screw about 1 3/4 out, it does bog when you just punch the throttle from idle, when i changed the mains to 280 it was backfiring from about half to full throttle, so i put the needle back to stock 3rd clip,, didn't change a thing, it doesn't seem to rip like it did with the 240's, shpuld i go back to them? when i checked the plugs they were wet with gas! can anyone help me with my jetting? i want to get rid of that bottom end bog when i punch the throttle and the backfiring,, the engine only has about 2 hours on it with new 60 over pro-lite pistons compression is around 230 on each cylinder