Hi, i have a 1986 honda shadow vt700 that is having trouble reaching high speeds. when i reach 55mph, the back cylinder just shuts down and eventually the bike does also. at first i thought it was a fuel problem so i cleaned the carbs. then i was told it was an electrical problem, so i changed all plugs and replaced the stator, and rectifier. i also swapped the coils and it was still the back cylinder that shut off. i am stumped.