Bizarre , Bike runs with battery disconnected

[Denisesewa]

Been working on my 1980 street tracker project, I stripped all un-needed electricals and rewired the bike, no problem runs and acts as it should, then I shortened and adapted a set of KXL 650 USD forks to it, there wasnt a convenient location on or near the bars for the ignition switch so I moved it next to the starter relay and decided to just interrupt the main power from the relay with the ignition switch, just took it for a test ride to check out the new forks and when I went to shut it off with the key it kept running, using the kill switch on the bars killed it,( also turning the lights on with the key off also kills it) so I set about testing, with the key off there is no power to anything except the battery side of the starter relay and the positive side of the ignition switch.I started the bike, unplugged the ignition switch, bike keeps running, I then disconnected the battery after starting the bike and the bike keeps running.
Correct me if I'm wrong but doesnt an alternator need voltage to excite since its not permanent magnets?
Since the bike has a Mikesxs electronic ignition is it possible that it requires such a low voltage to operate the alternator is putting out trace current enough to run it since it dies if I turn on the lights with the key off?
I intend to rewire the ignition switch to also isolate the ignition when off ( which is how I wired it when the switch was @ the handlebars) which will solve the problem but still, I'm Baffled.
Enlighten me please .

 

[TwoManyXS1Bs]

My XS1B will run without the battery, or with the fuse unplugged. Of course, it has to be running first. The rectifier's output feeds main power, red wire, between the ign switch and the fuse, so there's enuff power for the alternator's regulator and rotor. This is the standard proc on the early bikes, to adjust the regulator with the battery disconnected.

Now that you know that it 'can run', you need to look into your wiring setup to ensure that the ignition gets cut with the main switch...

 

[Denisesewa]

My XS1B will run without the battery, or with the fuse unplugged. Of course, it has to be running first. The rectifier's output feeds main power, red wire, between the ign switch and the fuse, so there's enuff power for the alternator's regulator and rotor. This is the standard proc on the early bikes, to adjust the regulator with the battery disconnected.

Now that you know that it 'can run', you need to look into your wiring setup to ensure that the ignition gets cut with the main switch...

Thanks for the explanation, I know when I changed ign switch location I tied the original ign switch wires together thinking interupting main power would kill ign so I know what to do to fix it.
Actually I was being lazy trying to avoid opening up the harness again.