If you've always used the left rear brake lever for starting the bike then you've probably damaged the switch on the lever when it was dropped. Try pulling in the right lever when starting the scoot.
If this doesn't work, have a look to see that your getting a brake light when you pull in either lever. When you do this you're creating a circuit which enables the starter to work. If you have no brake light, check if the battery or main fuse are banjoed.
Steo
November 2009