Aux light/Daytime lights bulb colour.

[Pat J]

Done a search and can't find a specific answer.
I am shortly going to be fitting a set of Hella Micro DE foglights as supplementary lighting on my GS as much for lighting up the edges of the road as well as visibility by other drivers. I remember a topic on a Harley forum about running yellow bulbs as well as better in fog they also catch other drivers attention better.
I actually ran a Lucas yellow bulb in my Harley and Dragstar headlights as both had aux lights to light up the road better. On the GS I have Osram Nightbreaker plus bulbs fitted in the headlight which I find a lot better than my Harley was with any bulbs fitted.
I currently can't afford to go down the Hid route so just after best solution available.

All help and advice appreciated as usual.

 

[Fanum]

There's a difference between colour, how much attention a colour attracts and how effective it is in helping you see.

YELLOW light has often been claimed as being able to 'penetrate' fog and rain further......which from what I could find out when I researched it a while back, appears to be unsubstantiated......

2. Do yellow fog lights work better than white lights?

I found this article saying yellow lights do not penetrate fog better than white.


http://www.gi.alaska.edu/ScienceForum/ASF5/593.html

Alaska Science Forum
March 3, 1983


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Do Fog Lights Really Work?
Article #593
by Larry Gedney
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This article is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Larry Gedney is a seismologist at the Institute.
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I was asked the other day why fog lights were yellow. When I couldn't come up with an answer, I started asking around and discovered, to my surprise, that apparently nobody else could either.

Skiers, shooters and other outdoor types have long known that yellow goggles or glasses enhance outdoor vision. This is because the yellow lenses filter out the blue part of the spectrum and increase the contrast of a scene. But does the same thing hold the other way around? With the goggles, we are filtering reflected light entering our eyes, but is it possible to illuminate something with yellow light and achieve similar results? The answer, apparently, is no (which is likely to raise strong objections from people who have been using yellow fog lights for years).

For expert advice, I contacted the Cold Regions Research and Engineering Laboratory (CRREL) on Fort Wainwright. Captain John Craig of that group then arranged to have a computer search made on the subject of light penetration in fog and mist from CRREL's headquarters in Hanover, New Hampshire. As a result, I obtained a list of over 200 references and abstracts of articles published by researchers all over the world.

Not a single one asserted that yellow light has superior penetrating qualities, but several specifically stated that it did not. To quote from one Russian article, for example:

"Investigations and practices of automobile traffic do not confirm any substantial advantages of yellow light over white light. The advantages ascribed to it may take place only in very thin fog or may be subjectively received by some drivers owing to their individual peculiarities of vision. Therefore, it does not make any sense to switch over headlights to yellow light, although the use of yellow light in special fog lights does not raise any objections." End of quote. The phrasing is quaint, but the meaning is clear.

I had long thought that the yellow sodium-vapor street lamps that are becoming common were used specifically because they cut through fog better. I found out that there actually is a specific reason for their use, but that it is because they operate on only about half the power of conventional lamps.

So, unless you just happen to like yellow, save your money and forget about so-called "fog-lights." They don't exist.

On the other hand, a set of yellow lights coming out of the fog at you will be sufficiently 'different' maybe, under certain situations, to grab a bit more attention from other drivers.


If you really can't afford HID (and you should look on Ebay to see how sharply the prices of the cheap ones has fallen) then maybe save up by putting some standard bulbs in rather than the fancy ones that claim so much but usually fail to deliver, and that often burn out a lot faster because they are running hotter or their filaments are more fragile.

I suspect that positioning your lights and maybe even masking some light spread off might be more effective........to see what I mean, try putting ALL of your lights on and High beams as well, in the fog, and all you'll see is a wall of reflected light......'FOG' lights are usually a very flat but wide beam that penetrates the fog further before being reflected back, so the beam shape and the light position seems to be more important than the colour or the wattage.

BTW, there is little point in putting much higher wattage bulbs in GS lamps........the traditionally poor (11XX anyway) light setup is due mainly to reflector design, NOT lumen output of the light source.

If you can afford Hella Micro De lights by the way, you could afford a dip beam HID and a pair of 10W cree LEDs as well.......that, IMO, would serve you far better

 

[Pat J]

The lights are from my mate for helping him out during the floods up here at the start of December. He'd bought them to go on a trike project he was accumulating parts for but everything in his garage was submerged during the flood except for a few bits on his shelves and insurance company are delivering a skip next week to list and dispose of the bits out of his garage and sheds.
Would a H3 Cree led bulb work alright in the Hellas?

 

[Fanum]

Would a H3 Cree led bulb work alright in the Hellas?

It would work in the sense that it would light up, yes.

I suspect (and this is just an informed guess mind) that it would be utterly pointless unless your prime concern was energy saving, which obviously it isn't on a bike.

LEDs are odd things........very directional light, and they need custom designed reflectors and projector lenses to become effective beams.(even though an H3 equivalent is likely to have multiple LEDs on its core)

The Hella lights will have reflectors designed for Halogen or all-round HID output patterns, so putting an LED bulb in is very likely (again, see my caveat) to result in a very poor spread of light, focussed in some places, large areas of 'missing' light and so on.

Stick with Halogen bulbs in the Hellas, but play with angles and mounting positions to best achieve whatever spread of light you are aiming for, be it fog visibilty, visibilty in fog (two very different things) or spot or flood light capability



LEDs are the future for lighting, but unless just a replacement for general lighting (dashboard illumination, pilot lights etc) they need to be housed in a very deliberate way........even indicator replacement panels have to have LEDs around the outside that are angled from the plane so that they are visible from more directions than 20 or so degrees off the vertical from that plane)

 

[Pat J]

Cheers for the quick informed replies I'll be putting some standard H3 bulbs in and will look at putting a Hid bulb in the dip beam in the near future. Only other bulb to change is the sidelight bulb as it's blown 2 in 4 months of ownership these were just regular bulbs nothing fancy so wondering if there is a good alternative led wise that works with the canbus warnings.

 

[Fanum]

Only other bulb to change is the sidelight bulb as it's blown 2 in 4 months of ownership these were just regular bulbs nothing fancy so wondering if there is a good alternative led wise that works with the canbus warnings.

More likely to be a poor earth than anything else.....take the bulb out, take the holder out (if it's possible on the 12, I don't know) and clean any sign of rust or poor surface contact with the side pins of the bulb up with some fine sandpaper.

TBH I don't even know if the canbus system bulbs are 'earthed' in the way that a conventional system is, but you can't lose anything by cleaning all contact surfaces up

PS yes, if the 'sidelight' is what I'd call a 'pilot light', just a permanent ON light that isn't meant to actually illuminate anything.......the LED equivalent should do the same job, and in theory be more stable/longer lasting, but it's still worth checking the physical connections thoroughly

 

[Bendy toy]

Ive got and LED "bulb" in my side/pilot light. Its worked well for at least 12 months and being very white does stand out nicely. The old filament bulb never lasted long and looked dim by comparison. I'm considering using LED "bulbs" in the aux headlights ("spots") but I already have HIDs in the headlight so I no longer need them for their road lighting ability.

 

[columbus]

Yellow bulbs are illegal on UK roads unless you are airside on an airport or the vehicle is an import.

 

[Grim Reaper]

Yellow bulbs are illegal on UK roads unless you are airside on an airport or the vehicle is an import.

<couch> Bollocks! </cough>
Yellow headlight bulbs fitted as a matched pair is within the acceptable criteria outlined by the vehicle operator & services agency (AKA VOSA).

From the The Road Vehicles Lighting Regulations 1989 Schedule 2,
7. Colour: White or, if incorporated in a headlamp which is capable of emitting only a yellow light, yellow

 

[columbus]

<couch> Bollocks! </cough>
Yellow headlight bulbs fitted as a matched pair is within the acceptable criteria outlined by the vehicle operator & services agency (AKA VOSA).

You need something for that cough.

There are no uk spec vehicles manufactured to my knowledge with yellow headlamps hence my point about imported vehicles. The reg you refer to, and which you have cropped to suit, states the front position lamp can only be yellow if it is installed as part of a headlamp which is only capable of emitting a yellow light.

A motorcycle can only have one front position lamp, another part of the reg you omitted.

I am unaware of any current BMW motorcycle that comes from the factory with a yellow headlamp.

The op's post refers to auxiliary front lighting which comes under the category of optional lamps. The reg you refer to covers position lamps whether obligitory or optional and to comply a solo motorcycle can have only one mounted centrally.

To save you looking you can read the complete schedule two here

http://www.legislation.gov.uk/uksi/1989/1796/schedule/2/made

If the lights are fitted as optional front fog lamps, optional as there is no legal requirement for any vehicle to have a front fog lamp, then you need to read schedule 6

http://www.legislation.gov.uk/uksi/1989/1796/schedule/6/made

This makes it much simpler especially for motorcycles as there are no limits on the number of lamps so unlike headlamps and position lamps two can be fitted. Fog lamps can emit a yellow light.

However fog lamps can only be legally used in conditions of seriously reduced visibility, driving rain or snow. Using them during conditions of normal visibility is an offence which can result in a conditional offer of fixed penalty of £50 ( misuse of optional lamps).

DRL's can only be white and must automatically switch off when the headlamps are switched on. This schedule is a bit shorter

http://www.legislation.gov.uk/uksi/1989/1796/schedule/3/made

What an individual wants to fit to there vehicle is up to themselves but the info is all freely available should they wish to read it.

As far as VOSA is concerned some of their checks are not compiled in such a way as to check the legality of using a vehicle on a road more to ensure it's safety. The best example of this is a new vehicle imported from say the USA where rear indicators are red and sometimes form the brake light. This results in a flashing red lamp to the rear when it should be a steady amber lamp. For an SVA this vehicle would pass the test but it still is an offence to use it on a road in the uk ( as a permanent import) and it will also fail it's first MOT. So just because VOSA say it is an acceptable criteria doesn't mean it is legal and before any one asks the above example was one I came across at work and was confirmed by the VOSA examiner I was working with.

I'm sure someone will let me know if I've missed anything.

 

[Grim Reaper]

I concur, schedule 2 applies to position lights, schedule 4 and schedule 5 however reference dipped headlights and main beam respectively, but the same applies, 7) Colour.. White or Yellow.
also..Motorcycles can have two headlights., but must have a minimum of one.
If you want to stand out from the rest of the lights on todays roads, fit yellow headlight bulbs (or tint the glass/plastic front lens)
I doubt you'd have any issues passing yellow coloured auxilliary lights through an MoT.

 

[columbus]

If you want to stand out from the rest of the lights on todays roads, fit yellow headlight bulbs (or tint the glass/plastic front lens)
I doubt you'd have any issues passing yellow coloured auxilliary lights through an MoT.

Standing out is now the main problem. Since the introduction of DRL's there is a proliferation of lights at all times of the day so bikes are blending in to the background. I saw the picture, a while back, of a transit with its lights on. A closer look showed the near side light was actually a bike headlamp with the bike almost totally blending in. The triangular pattern of additional lights on a lot of bikes seems to work.

Apparently a blue light stands out more than any other colour to the human eye. Have a look the next time you see one of the Artics lit up like a Christmas tree.