05 honda foreman 450. I,m having a hard time getting the motor to turn over easy. I've tried 2 good known battery's and 3 starters with 2 being brand new. With the spark plug in the motor will turn very slow and sluggish almost as if the battery is dead. With the plug out it turns over with out a problem. I have already replaced the solenoid, starter, battery, wiring and fuses. I have also hooked jumper cables straight to the battery. Any advice would be helpful and thanks.