'08 550 electric cut-out when revved!

[Seahunter]

My 550 Trail Touring starts & runs perfectly but, when I rev the engine whether on a stand or on the trail, the lights suddenly dim & the tachometer drops to zero. Let off on the throttle and things are fine again. The engine does not seem to be affected.
Any thoughts before I start ripping it apart?
Thanks for your time.

 

[850Switchback]

Voltage regulator is going bad.

 

[Mike-DRH]

That machine has 2 completely separate charging systems built into the stator, 1 for lights and acc., 1 for ignition. The ignition charging system has it's own internal regulator in the CDI box. The lighting and acc. system has a external regulator that will ground off any excess voltage. Either your regulator is going bad (as mentioned above) or you have a short somewhere. Depending on model and year the regulator is most often mounted just above the left foot-hold, inside the engine bay, and will have a single yellow wire attached to it, sometimes 2 wires, 1 brown and 1 yellow depending on model and year. The aftermarket regulators don't cost much, buy one and try it.

 

[Seahunter]

Thanks guys. I'm off to the garage. I have seen that regulator in the footwell & will remove it. I think the service manual has a method to check it but I may just replace it. I'll also check every connection on the machine, ground & live, to ensure they're all secure. Your suggestions make sense. Increased revs = increased vibration = increased likelihood of a loose connection.