Idles, dies under load KFX400

[AJOet]

I believe it is a 03, stock carb, 160 main, 25 piliot, 2.5 turns on a/f screw, k&n filter no lid, new plug, slip on pipe. It starts and idles good, choke functions properly, if you rev it in neutral it revs with out hesitation. If you try to drive it it sputters at 1/4 throttle or less and dies if you don't play with the throttle to get it past that point then it pulls hard. I also put fresh gas in, cleaned the carb, running the petcock in prime doesn't make a differance, and fuel flows good. My buddy just bought it so i don't know any history on it. Any ideas or help would great.

[weinzerl]

sounds like it might be a bad cdi box

[AJOet]

would that be only under load?

[weinzerl]

either that or check ur battery connections...last weekend i went riding and i had no power and it was almost like i was hitting the rev limiter at like 2000 rpms...looked it over and my negative battery cable had broke...as far as the cdi thats what i heard will happen if its bad

[Ride.Race.Live]

could also be your coil check your spark plug... any shorts in the wiring

[AJOet]

I cleaned the coil connections to the coil also. Didn't check the battery cables yet. Did yours start well even with the broken ground? Is there any other grounds to the frame that i should check? Thanks for any input!

[weinzerl]

it started and rode fine at first...i ripped up a hill and thats when its started cutting out...i think the broken ground wire was barely touching the terminal when i started off.. then it broke completely when i hit the hill