Fuel stabilizer is NOT a good cleaner.
Gumout or Berrymans B12 Chemtool are the best cleaners.
Your problem sounds more electrical, like a corroded or loose connection at the battery.....and looking and tugging isn't always good enough to test.
Or the aforementioned sidestand switch.
When someone says this:" it also cuts off when i engage the clutch." the sidestand switch is highly suspect.