Anyone know what the brightness requirements are for tail, brake and indicators? If indeed there are any?

Just trying to check if my LED strips are going to be bright enough

Thanks,
David

It's unlikely you or anyone on here will have the correct measuring device to test them.
A camera light meter on spot might do it but the eyes are very good so park your tintop next to the kit and get a couple of friends to press pedals

Well I can get the spec sheet for the LED strips I am using which quotes brightness in lumens.

I know fog light requirement is 100-400 lumens. But thats kind of irrelevant for the bike. I am interested in tail, brake and indicator.

I'll have a play with them next to my normal bike lights

Not sure on rules, but I like my brake lights nice and bright.

The biggest challenge with LED lights is that they tend to be very directional - a single LED usually has a very narrow viewing angle, and the brighter they get, the narrower the angle gets too. 5 degrees is not unusual and all the Lumens in the world won't make it more visible from the side.

Luxeon LEDs often claim to have 180 degree range but even this claim is dubious to say the least, and it takes quite a bit of creative reflector design to make the most of them. At the end of the day it is your eyeballs that will tell you if it is bright enough, but make sure you look at it under realistic conditions and from realistic angles.

I went through a whole load of different LED 'replacement' bulbs and they were, on the whole, crap & some were downright dangerous, offering very little brightness and even less angle of view.

I came to the conclusion that unless you are prepared to spend a couple of hundred pounds on a decent set of tail lights you will always find that they are not quite up to the job.

If you're talking about brightness for IVA it is all down to the tester on the day - & the criteria (if not E marked) is that they should display a similar light/brightness to an E marked unit. Unfortunately much depends on where they are being viewed etc & I have even heard of a failure for being too bright - I've also heard of a fog lamp failing (brand new E marked & with a standard 21W bulb!) for not being bright enough!
I use E marked led units on the Furore which I'm very satisfied with & have been fine at IVA, unfortunately they'd be ideal on the front of a 7 but not really right for the rear (both front & rear look identical until turned on, fronts have indicators/side, rears have ind/side/stop, but as they are on a rubber stalk might look a bit odd at the back of a 7!) They don't cost a couple of hundred quid tho'

Have to say all my experiences with LED lights have been poor. As above comments re the narrow angle also the colour balance is towards the blue end of the spectrum and subjectively they are about a quarter as bright as filament bulbs with the same claimed lumens.

Bought some and chucked in bin they were so disappointing. Seems to be a led thing rather than a quality issue as my kitchen led's are also poor and will be replaced as soon as I can be bothered.

Cheers

Hmm - this is for the bike, not a car and I have yet to see any rear lights that will fit in the space I need other than the LED strips.

These are the strips I have at the moment:


Rear lights 3

They seem quite bright.

I basically need to fit my lights into a space no more than 300mm wide and 20mm high

(It was probably me you heard about failing for lights too bright - my first SVA test and the front indicators were deemed too bright even though they were e-marked)

Sorry to say I doubt if they would be bright enough for IVA or even Mr Plod
What are they like from a side view?

Its quite tricky to get a decent photo of them to be honest, the strip is rated at around 200 lumens. Brightness doesnt tail off much from a side view.

What do the manufacturers using LED lights do?

If the IVA place was closer I would pop in and ask the question.

They either tend to use lenses to diffuse the light or they are 'fired' at different angles into a reflector ~ or sometimes both. It might be worth taking it down to your local mot station and having a word

Am I the only one that feels that ESPECIALLY on a motorbike you'd want to go above and beyond what the law requires in terms of brightness and thus visibility? Style is all well and good, but safety should come first, right?

I agree, this is a bike for fair weather and daytime use predominantly though. So I am afraid its mostly about the style than function.

I think what I will do it mock up a complete light unit and then see how it looks and works and also take it around a few local MOT places to see what they think to the brightness etc. The LED strips are very cheap, so it doesnt matter if it doesnt work from a cost persepective, its more a pain in the arse as I would need to fit addtional lights for sva.

David

I have just got some prismatic lens plastic in flat sheet to have a play around with as well.

The plan was always to have it behind some sort of lens anyway to protect it.

I am going to mock up a light this weekend to have a play with.

David

Take 2. This strip is nearly double the brightness of the original stuff. Each SMD LED actually has 3 inside it.

These pics are taken in daylight, with the strip mounted above the rear light of my normal bike for comparison purposes!

Tail light:

Rear lights take 2 - tail

Brake light:

Rear lights take 2 - brake

Now what do we reckon?

Its certainly bright enough to leave you seeing spots....

The light certainly seems quite bright but it is only a few percent of the surface area so is it actually an equivalent brightness given that fact? (playing devil's advocate here) I remember at my SVA they were debating whether the LEDs I had fitted were up to the job and in the end they passed it on the fact that the reflector and lense diffused it sufficiently to be deemed as 'suitable'. I was nearly shunted up the rear a couple of times by drivers who didn't see my brake lights - it was then that I decided an upgrade had to happen before I got seriously hurt.

A bike's surface area is much less visible than a car and even my Goldwing Aspencade which was decorated with 3" wide strips of bright red light across the rear and pannier sides, still got narrowly missed at times - it seems that car drivers (some anyway) need to be spoon fed with visiblity

Maybe your prismatic lense idea would be a good step forward to spread the light around a little more


[Edited on 12-11-10 by RazMan]

There is no legal minimum size for any lights that I can see in any of the regulations. I understand the comments about visibility though - form over function though and all that at the moment.

I will mock up a light with a lens in a week or so, and see how it goes. Its still only going to be 20mm high, but the lens would diffuse the light and spread it across the whole area a little more. I will also paint the inside of the housing with chrome effect paint to reflect the light as well.

Well its a nice little side project