79 T140E Electrical issues

I hate electrics!! Mainly 'cos I don't understand them too well. However ...
... is your bike a US market machine? I ask because at that time bikes sold into the US market had to have indicators lit all the time as 'running' lights. Having said that the headlight should be permanently lit as well, without an on/off switch, I do believe. I can't help thinking that you may have something of a 'halfway house' wiring set up.
It could also be bad earthing of the indicators themselves (or anything else for that matter!! Told you my understanding of electrics is woeful) as I seem to think I've heard of wires being run from the indicator stalks directly to 'earth' when indicators don't work properly.
Just a couple of ideas from your local, but well meaning Luddite.

 

Hi Gaffer I think the wiring you have connected your indicators to are side markers which illuminated with parking lights.

 

Have you checked wiring from indicator turn switch ?

 

Hi the wiring at switch you may be able to check colours of wires and follow wiring run.

 

These youngsters haven't lived I have forgot more than they will ever know