Yeah, I'd up the idle a bit. As mentioned 1100 rpms is the factory setting, manual says 1100-1150 (not sure how to measure that extra 50
With my (stock) bike I had to switch off my running lights if I was stuck in traffic or at a long light with the bike idling as it would go below 12.9.
A good reason not to let your bike idle for too long. These Vulcans like to rev, so wouldn't hurt to get a voltmeter for your bike so you can monitor what's happening...