Headlight color changing

[crtsteve55]

While riding with another rider ahead of me he noticed my low beams alternated blue to white. Is there an explanation?

[Knizar]

While riding with another rider ahead of me he noticed my low beams alternated blue to white. Is there an explanation?

What R U riding?

[pegasus1300]

Profile says 2013 and picture is an RT

[cyclekid58]

Low beams do that when you encounter any bumps from the up/down movement. Caused by your visual line dipping behind the shutters. I run with high beams on all the time during the day which gives you better visability to be seen and eliminates the look like your headlights are flashing.

[ARtraveler]

As cyclekid58 said above.

Riding on bumpy terrain will cause the headlights to seem to flash. High beams on all the time seem to solve the issue for me.

[Peter Aawen]

While riding with another rider ahead of me he noticed my low beams alternated blue to white. Is there an explanation?

Courtesy of Bill Sistrunk on Quora.com


Headlights used to be a simple incandescent bulb with a glowing filament providing a yellow or orange tinted color. Then we learned about halogen gas.

Halogen bulbs last longer and create more lumens of light per watt of power than does incandescent bulbs. They also are much hotter and create light that is much whiter than incandescents. When compared to the yellow/orange of an incandescent, they appear to be more bluish in color.

These bulbs are also more compact. These smaller bulbs allow for a more focused and tight beam of light. [When your headlights are dipped] this light is directed down to the road surface and less up into the area above the road.

When you combine these attributes, you will have a situation where less of this blue tinted light is in the eyes of oncoming drivers when on a level driving surface. If the front of the vehicle lifts as it crosses a rise [or bump] in the road surface [something the short wheelbase of our Spyders/Rykers exaggerates] then the focused part of the light can become aimed directly into the eyes of other drivers. The result is a brief increase in this bluish light being observed by oncoming drivers.

[My edits for clarity]

And...

There's also the 'prism like' action that Projector type headlamps add to the edges of the light beam passing thru the thick part of the projector lens vs that passing thru the thinner part of the projector lens around the edges - the lens thickness variation acts like a prism and separates the individual colours in the bright white light emitted by the globe. That's why the headlight colour seems to change a little towards the blue/purple when you view it from a different angle &/or when the oncoming vehicle hits a bump or rise in the road so that you get to see the light emitted by the projector lens at that different angle...

Then there's the differences in colours caused by the type of LED used or surface coatings on the globe of other types of lamps to take into account too. White LED's are often basically just blue LEDs with a phosphor coating on their surface, which converts the energy received from a blue beam to that 'bright white' colour that many mistake for a better beam &/or range. In some of the cheaper LED's out there, the coating is not that great &/or effective, which results in even more of a blueish tint to the resulting light output than from the more expensive/better quality LED's.....

Add all that to the short wheelbase, low mounted lights (especially in Aus/NZ spec Spyders, where our Low beams are where the North American Fog Lights are! :rolleyes: ) and the way that our front suspension reacts to bumps & rises (see Bill's explanation above) and you get those flashes of blue people see from our lights - more so from our Spyders/Rykers than from most other cars cos unlike those cars etc, we've got all of these effects bundled up in the mix, not just some! :thumbup: