Modern Vespa

I have a Vespa lx 50 2t 2012 and since the day I got it the lights weren't that bright but I didn't look into it. One day I had to go down a tall step and when the scooter dropped the light shone bright for 10 seconds, since then when I start it if I stand up the lights are bright and if I sit they dim again. After 1 minute from start it doesnt make a difference. Anyone know how to fix this or had a similar problem? Any help is welcome

Do you notice any change of revs from the motor when that happens?

The lights are fed from the AC regulator, but this can't regulate properly without the battery being connected. Check the battery connections.

If you leave the lights bright they will burn out - they are dim normally.

The engine stutters when its cold but I dont notice anything else

I dont know about that because I have compared it with a similar model and the lights are brighter on that compared to mine. Should I open the battery case and take a look at the connections?

Yes, as jimc says, check that the battery connections are clean and tight.

I only asked about the revs to rule out an air or fuel issue that could be messing with the idle speed. That doesn't seem to be the case so I'd go on to the battery, then the regulator.

Anyone know the best carb settings for this exact model? (how many turns out for the mixture screw)