Bright idea: BMW's new headlights see round corners
Riding in the dark highlights an innate problem with traditional headlights – when you lean into a turn the beam is angled away from the direction you’re trying to go.
Related articles on MCN
- BMW create maintenance free chain
- How nuclear subs gave us titanium exhausts
- Time for a two-stoke comeback
It’s a particular problem on dipped-beam. They’re angled downwards towards the road so as not to shine in the eyes of oncoming drivers, but when your bike leans into a corner, that downward tilt means they’re directed towards the outside of the corner just as you’re looking towards the apex.
There have been plenty of attempts to tackle the issue, but the adaptive headlights developed for the 2021 BMW R1250GS provide the simplest and most convincing solution yet.
BMW have been pursuing the goal of adaptive headlights for decades. The firm were patenting ideas to solve the problem as long ago as 1980 and a decade ago, in 2010, introduced their first production solution on the K1600GT.
Back then, BMW’s idea was to reflect the halogen headlight beam on a moveable mirror, controlled by servo motors to change the beam’s position on the road in relation to the bike.
More recently, on the F900R and F900XR, BMW took another stab at the problem, using the more modern technology of headlights incorporating multiple small LEDs. Extra LEDs with reflectors directed to point their beams in different directions are lit depending on the bike’s angle of lean, manipulating the beam pattern to assist in corners.
But the latest solution, debuting as an option on the 2021 GS and followed by the R1250RT is both simpler and better. It steers the dipped-beam headlight into the corner, while simultaneously keeping the lamp itself level with the horizon regardless of the bike’s lean angle (up to 35°).
The RT system uses a simple servo actuator that moves in and out as the bike leans. Teeth on the servo arm interlink with a cog on the outside of the rotating LED unit to keep the lamp level with the horizon. The GS will use a similar system.
The headlight actually uses the same LED low-beam lamp as the standard unit, simply adding the swivel mechanism into the mix so the LED can remain level and point towards the inside of bends.
BMW have also added a third axis of movement, allowing the light to tip up or down by a couple of degrees to compensate for pitch changes caused by acceleration, braking or loads.
On the R1250GS, the system costs an extra £590 but can only be added along with daytime running lights and Dynamic Package for a total cost of £2100. On the RT, the adaptive headlight also costs £590 but comes with other equipment that brings the total cost to £925.