My 2006 HD EG Std is having charging system problems which just began. Caught in heavy traffica dn voltmeter dropped off to 9 V with engine and charging light coming on. Rolled on throttle and charging went up to normal 15 V. A weak later again in moderate traffic voltmeter dropped to 9V but now it takes longer with RPM at 3000ish to get voltage back up. Bike even went dead today after I stopped at a short stop. Engine off. Any ideas?

 

Could be a few things, but start with the easiest. Your idle is staying up around 1k right?
How old is the battery? If its original, that would be my first suspicion. You can load test it to be sure. Just take it down to your local battery shop if you don't have a tester. Most will do it for you.
Go through the routine steps in checking the charging system, just to be sure. Voltage across the battery with bike off should be 12.5 or so. Voltage with bike running at decent idle should be up around 13.5 or so. I'd also pull the stator plug, yours is easy to get apart, and check from each terminal to ground with ohmmeter. If either leg is grounded, then stator is junk. If not, run the bike with stator unplugged and check AC voltage across the terminals of the stator. You should get increasing voltage up past 35 volts.
have fun

 

Thanks will do on day off tomorrow. Battery is second on bike. Changed two years ago. Bike does stay at 1000 rpm except on the day that the problem originally showed up. Idle down to about 600 rpm while stuck in traffic.

 

Anything under 1,100 rpms will give you a dramatic drop in recharge voltage.

Bike dead ... check your primary battery connections. Even the slightest corrosion, or looseness will give you these issues.