Gandikota is situated at a distance of around 300 Km from Bangalore. It takes around 6 hours from Bangalore to reach Gandikota.
There are hardly any public transports available from Bangalore to Gandikota. So you can either go by your own bike or car or if you organize any trip, you can go by a rented vehicle like Tempo traveler. But remember that, you will have to pay an inter-state tax of around Rs. 3500 for entering into Andhra Pradesh from Karnataka for a tempo traveler.
There are different charges for different kinds of vehicles. The inter-state tax has to be paid near Kodikonda on the way.
Gandikota is 15 km from Jammalamadugu town of AndhraPradesh in Kadapa district. You can ask any local about the Gandikota and they should be able to guide you to the Gandikota.