Honda Grom electrical issue

I have an electrical issue with my bike. When I'm in neutral, from time to time, the neutral light flickers. If the neutral light is flickering the start button doesn't cause the starter motor to turn over. This used to happen just the odd time, but the problem is getting more frequent as time goes by. It's obviously some kind of electrical connection problem but I'm struggling to understand it. All lights work perfectly, the fuel pump primes every time. I checked the connections to the battery they were good and bright but cleaned them anyway. Same with the cluster of earth wires under the seat. It seems that there's some kind of connection problem in an area that the neutral light and starter switch, or perhaps the starter motor itself, share.

Any idea on this?

Cheers

You most likely have a bad connection in the neutral switch or the wiring or connector going to it. When it's in neutral the switch is closed and that gives a path to ground for the starter relay and the neutral light. If there's a bad connection in the neutral switch, wiring or connector going to it the starter relay will lose it's ground and the starter won't spin. I'd check the connector going to it first, then the wiring, then the switch. You could also short the switch with a bit of wire into the connector going to it and see if that solves the problem. If it does then the problem is the switch. If you short the switch the bike will be able to start in gear so be careful with that.