Daniel Stern Lighting Consultancy and Supply
For mechanical-aim headlamps, you will have to do your best to place the top edge of the low beam 'hot spot' on the applicable horizontal line per the table above.
These instructions are applicable only to European ECE low beams, because US DOT VOL and VOR headlamps cannot be visually aimed horizontally, and in many cases, cannot be aimed horizontally by any means at all, because no provision for horizontal aim adjustment is provided. [This is because US regulators believe there is no way to define a visual cue, such as a kink in the cutoff, that would allow accurate left-to-right placement of a headlamp beam and that cars will not get in fender-benders that will knock the headlamps out of horizontal alignment. For what it's worth, the Europeans have been successfully aiming their headlamps vertically AND horizontally since 1955. -ed.]
European ECE headlamps have a "kink" or "elbow" at the top of the center of the beam pattern, where the cutoff bends upwards. Adjust each headlamp so that the kink lines up (left-to-right) with the +C mark for whichever headlamp you're working on. The tolerance here is +/- 2 inches of point (c). Slight leftward aim (-1") increases seeing distance down the road, but excessive leftward aim increases glare to oncoming traffic.
Here is what a correctly aimed set of European ECE or US DOT VOL headlamps looks like on low beam:
And here is what a correctly aimed set of US DOT VOR or mechanical- aim headlamps looks like on low beam:
12/04/2006 01:48 PM
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