New & also in need of help

[XJ600 1990]

Hi all,

I have a xj600 1990 and its not starting. I have cleaned almost every contact and checked every connection & wire but it still will not turn over. When I turn the ignition on, I get a green light to indicate neutral, both indicators, horn, brakes and front & rear lights work. I don't get the normal red oil light indicator either when pressing start. I have cleaned the kill switch, start button assembly and the clutch sensor (under lever) but still no luck. This would leave me to believe I either have a bad earth or part of the ignition system is failing, I don't think power is getting to the switch. It's worth noting, I have tried a new battery but to no avail.

A little bit about the bike... Its done 6000 miles, the second cylinder wasn't getting hot when purchased, but the bike started and turned over fine. I have cleaned the carb and the bike runs a lot better (needs tuning though). I went for a 20 minute ride yesterday. In the evening I wanted to get the lights working in preparation for its MOT, since changing to the led head lamp the tailgate and headlamp hasn't work (wasn't ever able to check due to battery being out whilst rebuilding carbs). At some point after tweaking the front wiring loom and the fuses the lights came to life. I am not sure if any of this is relavant but this morning I tried to start it for its MOT and couldn't get it started and so here we are.

I am very, very confused. I know I need to get a multimeter and check the values but does anyone have any ideas as to what's going on?