Lamborghini released today a promotional clip for the madness that is the new Aventador J speedster. The Aventador J is working one off vehicle, which had its world debut this week at the Geneva auto show. It has no roof and no windshield, but at the same time it has 6.5-liter V12 engine, which is able to take it up to a top speed of 350 km/h. You need a helmet to drive it, of course.