2004 R1150RTP starter drop off issues

[BILLK75]

On my 2004 dual spark R1150RTP, when you hit the starter button the starter spins but the solenoid does not engage or the starter will engage and turn the engine over and then the solinoid drops out, or it works normally. Any ideas? I have changed the starter with a new one and replaced the starter solenoid.

 

[gsaddict]

Check all upstream connections starting with power cables on the battery and engine block negative (hard to get at under the battery box)
Control wiring is next.