Is it legal in the uk to make my own LED rear light for a motorcycle?

Hal Stetler

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[h=1]Is it legal in the uk to make my own LED rear light for a motorcycle?[/h]i live in the uk and ride on a provisional licence. i am currently studying motorcycle mechanics and i am about to embark on a honda c90 project bike and wan to make my own LED brake, tail and indicator combo light for the rear, is this legal, and if so is there a certain brightness i need? thanks :)
 

-Virgil-

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Homemade lights are not legal or safe on roadgoing vehicles. In the UK, all vehicles first registered after April 1985 must be equipped with "E-marked" (ECE type approved) lamps and bulbs.
 

Hamilton Felix

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As a motorcyclist (here in the US of A), I was interested in LED lights. All but the very largest motorcycles typically have tiny charging systems, so "more light from less power" sounded good. Motorcyclists always want to be more visible. But even before I learned it's not legal to change the type of light source, I found out that most of the LED drop-in bulb replacements did not make more light, only seemed bright in a particular direction. The only LED "cluster" that looked like real competition to the factory bulb was so bulky I'd have to do major surgery on my light (lose part of the reflector) and it still wouldn't be legal.

I think the best approach is to keep the stock lights as clean as possible and fitted with the best quality bulbs available. Then add a few lights. When I look at the really serious touring types on their late model Goldwings, they generally have not messed with factory lights, just added a few LED lamps or strips to their hard luggage and otherwise improved "conspicuity" while keeping their motorcycles legal.
 
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Alaric Darconville

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When I look at the really serious touring types on their late model Goldwings, they generally have not messed with factory lights, just added a few LED lamps or strips to their hard luggage and otherwise improved "conspicuity" while keeping their motorcycles legal.

Just so long as the conspicuity does not add ambiguity.

The rider should always ride as if they were driving. Passengers ride, drivers drive. Drivers should assume that the other drivers, and especially "riders", cannot see them, and cannot hear them, and that when they CAN either see or hear them that they are out to GET them. This means driving like you want to get there*, not aggressively, but defensively.

The loudest pipes and the shiniest chrome and the brightest lights and the most protective of bandanas are not safety devices like a skilled and conscientious driver.

*Drive like you want to get there means driving in such a way that you survive the trip, not "driving like you want to get there first"
 

Diesel_Bomber

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I saw a bumper sticker that said "If loud pipes save lives, imagine if you actually learned how to ride that thing." Still cracks me up.
 

-Virgil-

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Just so long as the conspicuity does not add ambiguity.

+1 to that! Many (most?) homespun lighting "upgrades" on motorcycles, made with the best of intention to improve safety, actually have the opposite effect.

This means driving like you want to get there, not aggressively, but defensively.

A good word is "assertively".

The loudest pipes and the shiniest chrome and the brightest lights and the most protective of bandanas are not safety devices like a skilled and conscientious driver.

True. It is impossible to improve motorcyclist safety with loud exhaust pipes or flashing headlights. It has proven elusive how to improve motorcycle safety by means of lighting devices. It's possible, though; the newest research finally has shown a real safety benefit to certain lighting configurations (in brief: linear LED arrays -- white front, amber side, and red rear -- arranged so as to highlight the shapes that make the motorcycle identifiable as such. This means white ones more or less horizontally as widely spaced as possible on the handlebars and vertically on the front fork legs, amber ones facing sideways on the fork legs and rear fenders, and a configuration aligned with the bike's main visual lines at the rear, facing rearward. These should be lit day or night whenever the engine is running. The front and rear ones should not flash; the side ones may be wired to flash with the turn signals but should light steadily when the signals aren't in use.

The other enormous safety benefit for motorcycle drivers: light/bright colored helmet, clothing, and bike. A very large study of actual crash data a couple of years ago showed bright/light colored bikes and drivers are six or seven times (not percent, times!) less likely to be involved in a crash compared to dark-colored bikes and drivers.
 

Hamilton Felix

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Interesting.

I've had the "loud pipes" BS demonstrated: overtake a thunderous Harley with pipes so open it's just hammering you, and the moment you pass it the sound vanishes.

I have avoided the headlight pulsators. Oh, I've used pulsating/flashing headlights, but I was driving an ambulance at the time. I have no quantitative idea what a pulsator does to bulb life, but I'm sure it's not good.

Another note on noise: those who have been there can tell you that even a siren is only good for one or two car lengths when approaching a closed car at freeway speeds.

I'm big on visibility, but have finally realized that sheer quantity of light is not the answer (it took me a while, but I learned from an interesting study or two on emergency vehicle lighting). Vehicle lights need to convey a message, not massive confusion.

That bit about the LED arrays is fascinating. Many riders want to add "dimension" to their motorcycles, let other drivers see some size instead of simply a point source of light. It's common to try to add a horizontal "bar" of red light to the rear, often on trunk or side bags. And when I think about it, many motorcycles have far worse side lighting than.. well, pretty much any 1968 or later automobile.

To touch on the original issue, one selling point (yep, actually heard it from a Cadillac salesman) of the LED rear light is that an LED brake light comes to full brightness virtually instantly, while the incandescent lamp takes about 0.4 seconds to come up. Thus, the LED brake light gives the driver behind you an appreciable fraction of a second earlier warning.
 

Alaric Darconville

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To touch on the original issue, one selling point (yep, actually heard it from a Cadillac salesman) of the LED rear light is that an LED brake light comes to full brightness virtually instantly, while the incandescent lamp takes about 0.4 seconds to come up. Thus, the LED brake light gives the driver behind you an appreciable fraction of a second earlier warning.

The major filament of an 1157 produces 32lm at 12.8V, according to Don's Bulbs.com.

At 12.8V, it'll take an 1157's major filament 259ms to reach 90% of intensity (or 28.8 lumens), and ultimately about 400ms to reach 100%.

At 12.0V, it'll take 282ms to reach 90% of the intensity that can be reached at 12.0V (which is 25.7lmn), so you spent longer getting to 23.1lm than you did getting to 28.8lm thanks to the voltage drop. On a passenger car, will we see such a voltage drop? I hope not-- but it can still happen.

On a vehicle towing a long trailer, there certainly will be drops due to the extra wiring and the quick plug-in connector in most vehicles' "Tow Package".

An LED's rise time is not affected by this at all, giving it a definite advantage on longer vehicles, and vehicles with reduced voltage in general.
 

-Virgil-

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That is quite correct about the LEDs giving more or less instantaneous rise time versus the slower rise time of an incandescent bulb (which gets slower with reduced voltage). Be cautious, though -- this is not a justification for installing an "LED bulb" in a lamp meant to take a filament bulb. The theoretical safety advantage translates into practice only in a properly engineered and built LED lighting device. Fortunately for the DIYer, there are many excellent such LED lighting devices that can be successfully retrofitted to vehicles originally equipped with bulb-type lamps. I am talking about the standard-size truck/bus lamps. There are 4" circular units, 3" x 5" and 4" x 6" rectangular units, 2" x 6" oblongs, 7" circular, and a few other sizes. With some thoughtful creativity, some ready-made mounting brackets (or water-clear optical-grade epoxy if one is "planting" the LED unit directly behind the rear face of the existing lamp lens). If you do this, be sure to mock up your installation before finalizing it (with epoxy) to make sure any retroreflector built into the existing lamp lens does not interfere with the light distribution from the new LED lamp.
 

Marcturus

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The other enormous safety benefit for motorcycle drivers: light/bright colored helmet, clothing, and bike. A very large study of actual crash data a couple of years ago showed bright/light colored bikes and drivers are six or seven times (not percent, times!) less likely to be involved in a crash compared to dark-colored bikes and drivers.
But how much of this is due to self-selection ("safety-conscious" rider group vs. "mean-lookz" group)...?
 

Marcturus

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Find and read the study; this is discussed.
Can't find anything resembling "one-sixth" figures in the one from Auckland,
"Results -
Crash related injuries occurred mainly in urban zones with 50 km/h speed limit (66%), during the day (63%), and in fine weather (72%). After adjustment for potential confounders, drivers wearing any reflective or fluorescent clothing had a 37% lower risk (multivariate odds ratio 0.63, 95% confidence interval 0.42 to 0.94) than other drivers. Compared with wearing a black helmet, use of a white helmet was associated with a 24% lower risk (multivariate odds ratio 0.76, 0.57 to 0.99). Self reported light coloured helmet versus dark coloured helmet was associated with a 19% lower risk. Three quarters of motorcycle riders had their headlight turned on during the day, and this was associated with a 27% lower risk (multivariate odds ratio 0.73, 0.53 to 1.00). No association occurred between risk and the frontal colour of drivers' clothing or motorcycle. If these odds ratios are unconfounded, the population attributable risks are 33% for wearing no reflective or fluorescent clothing, 18% for a non-white helmet, 11% for a dark coloured helmet, and 7% for no daytime headlight operation."
http://www.bmj.com/content/328/7444/857.full
(I'm not claiming its methodology were adequate either, or its findings anything to write home about.)

urban camo pattern:
http://www.emlra.org/images/photos/Berlin_Brigade_chieftains_parade.jpg
 

-Virgil-

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Can't find anything resembling "one-sixth" figures in the one from Auckland

Wrong study; the one I refer to was a pan-European study based on crash data. And yes, the one you found is pretty questionable. That phrase "self-reported" raises all kinds of (fluorescent?) red flags.
 
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-Virgil-

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I found the one I was thinking of and have posted it here. I did not recall the numbers correctly; the approximated relative risk factor is not 7, it's between 3.89 and 8.47 depending on the sample group -- see Table 4 on the last page.
 

yorkie_chris

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For the MOT test I wouldn't worry about it if you were keeping the stock or at least some E marked housings.

In practical terms even with non approved housings then you're unlikely to be bothered. And you'd have to try really hard to make anything much worse than stock.*



*Unlike all the people with perfectly legal, E marked, incandescant, mini indicators that are as much use as a chocolate teapot.
 

AnAppleSnail

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And you'd have to try really hard to make anything much worse than stock.*

Sometimes it's tough to appreciate the work that goes into what highway engineers do. For example, just this week I was in (a Virginia, US) town at a left turn and complaining at how far back I was from the intersection. It's a protected left turn, but I still like to see what I'm turning onto. Yesterday I saw a large truck turning there (Tractor-and-trailer type). He pulled into the intersection, wheeled around, and finished his turn with feet to spare before he hit the cars in the recessed turn lane. Things that seem darn inconvenient are there for your safety.

Vehicular lighting is one such system. Generally they could be better, but are presently pretty darn good at what they do. Their required goals include:

1. Never dazzle a driver. But be bright enough to see all the time.
2. Never impair other drivers' vision under reasonable driving conditions.
3. Be visible in many directions while maintaining 1 and 2.
4. Durable and reliable for dozens (lamps) or hundreds (Other lamps) or thousands (Lamp housing) of hours while managing 3.
5. Consistent with all existing signal lights (More red = stop, Red & white in US means reverse, yellow blinking = signal) in tint, pattern, and spacing while managing 4.

Manufacturers often add more requirements, such as:
6. Low enough power draw for the vehicle in question.
7. Good airflow and appearance on vehicle.
8. Cheap to manufacture.
9. Reasonably easy to install/replace.

Highway engineers in most civilized countries have fairly strict rules about lighting systems to ensure compliance with all these. There is not yet a system that would account for time-of-day glare or wetness-of-road directional control to significantly improve signal performance cheaply. Until then, don't knock what works!
 

jamie.91

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I'm not sure but the way MOT's are going I'd say if its not illegal it soon will be

You should enter your cub in the the 90 challenge at Anglesey 90 challenge next time around ;)
 

kingofwylietx

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Fortunately for the DIYer, there are many excellent such LED lighting devices that can be successfully retrofitted to vehicles originally equipped with bulb-type lamps. I am talking about the standard-size truck/bus lamps. There are 4" circular units, 3" x 5" and 4" x 6" rectangular units, 2" x 6" oblongs, 7" circular, and a few other sizes. With some thoughtful creativity, some ready-made mounting brackets (or water-clear optical-grade epoxy if one is "planting" the LED unit directly behind the rear face of the existing lamp lens). If you do this, be sure to mock up your installation before finalizing it (with epoxy) to make sure any retroreflector built into the existing lamp lens does not interfere with the light distribution from the new LED lamp.

Hmmm.....my rear signal lights have a large where the lens is clear and there is only flat chrome behind it. If I read your post correctly, I can put proper/legal lights behind the lens (mounted into the chromed area) and be legal. Please confirm, I'd love to do something with that area. If you want to see the area, it is a 2011 Dodge Durango. The area I'm talking about is on the liftgate. It is a very large area in the tail light that looks like they forgot to put something there.
 
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