The standard headlamps on the Roadster are often said to be inadequate. Although the fortwo uses the same OEM H7 bulbs as the Roadster, there is a slight improvement but not much. If you feel that your lights are not up to scratch you have several options. We have tested 3 options, HID retrofit, Osram Nightbreaker, and Osram Silverstar.
The HID option is the most expensive, and offers the most style. The light is much more intense and generally will have a blue tint. The HID kit consists of a capsule, and either a combined starter/ballast, or 2 individual units. With HID kits you most certainly get what you pay for, and kits range from less than £100 to more than £1000. Legality is a subject that follows retrofit HIDs, many Roadsters with retrofit kits have passed MOT tests without any issue if the lamp unit has been adjusted appropriately after installation. fortwos, however, may not pass MOT tests with HIDs as the beam cannot be focused as well as the Roadster's projector lenses. Some issues have been also been seen with the cheaper kits from lamps not starting, through to flickering and loss of intensity.
The Osram options include the Nightbreaker and the Silverstar. The Nightbreaker capsule has a silver cap and 2 distinctive blue bands. The Silverstar is Osram’s older offering in its performance line and simply has a silver cap. Osram claim the Nightbreaker to have a whiter appearance, in our tests it was almost impossible to distinguish the difference when lit between the Nightbreaker and Silverstar, although light output was impressive from both. The light is yellow when compared with the output of an HID system.
Guides for changing the headlights can be found here for the fortwo 450, here for the fortwo 451 and here for the Roadster.