Probably worth checking the clutch and neutral switches operate properly (as well as the side stand switch). Also check their connectors too. If it got better when you bypassed the sidestand switch, but the trouble came back again, it might be that you disturbed some damaged wiring/loose connector at the same time.

By any chance will it start if you pull the clutch in?

It does sound very much like something in the start inhibit system causing the problem, which all of the above three switches play a part in.

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