Honda-SOHC

Good Evening Gents.
This is my first post here, so nice to meet you all and greetings from Poland! I have recently picked up a K2 from USA and I am slowly fixing it and putting it back to the original state.

I do have an issue with the turn signals. Whenever I push the turn signal switch all the way, the signal stays on constantly without blinking. But when I move it only slightly, the flasher works normally and the indicator works as it should.

I have checked the original relay, and also bought a new one. When I installed the new relay and moved the switch slightly,the signal didn't blink at all. So I went back to the old one, which worked half way through.

I did check the indicator lightbulbs, they are all 21W and signle-fillament.
I have also cleaned the contacts in the indicator switch, but the problem persists.

I have seen various statements that this should not be this way, and others saying that this is normal for the US models from that time. Could you please help me out? Much oblidged!