[QUOTE="MrMoped"] Simple physics really! When switched on, the headlamp assembly pushes the light beams forward (this is particularly noticable in the absence of daylight), this is called an action. So using Newtons third law which states that for every action there must be an equal and opposite reaction, the same force applied by the headlamp to push the light beams is then also applied to the vehicle, pushing it back! Extra petrol is used to overcome the force applied by the headlamps. [/QUOTE] [applause] But you've got red ones pushing you from behind and EVERYONE knows red ones are faster!