LED rear light problems ........ anybody else had a problem?

Message

HowardQ · #1 Post by **HowardQ** » Tue Aug 28, 2007 9:26 pm

Fitted a rear light lens, one of the second batch that Greg produced, so quite a while after some of you lot.
Not doing too well on LED bulbs at the moment.
Longer bulb life seems to be about 200 miles at the moment.
Started bad when ordered a pair of 18 rear facing plus 6 side facing LED units, cost me 20 odd quid with postage on tinternet. Turned up as 16 LED rear facing units! Complained that they weren't what was advertised, but gave me some bullshit that stock was constantly changing and that's all they had in at the moment.
Couldn't wait to get the dark tint rear lens on, so decided to try em. Not too bright, particularly in daylight, but not too bad, lens looked great on a black Falco, (THANKS GREG!).
Second time out on the bike the right hand unit failed on the brake light, normal rear light LEDS still OK. Checked everything out, put standard bulb back in to test ..... perfect.

Not too happy, so looked for some more local, heard they sold them at Halfords, so off I went. They sell 24 LED units, (still rear facing only), for £12 odd a pair, so saved 10 quid and got brighter units.
Were brighter on the bike, but still didn't really light up the reflector as they would with some side facing units, but were better.
Second time out on the bike, this time I lose the stop light LEDs, again on the right hand side, again standard bulbs still work perfect.

So left hand side, no problem, but right side has lost first rear light LEDs then the Stop LEDs on different bulbs.
Is it down to vibration? Then again, the original bulbs never failed in 16k plus miles.
Is this what I can expect with low wattage LEDs?
Anybody had a similar problem, getting pigged off at the moment?
Anybody know if they still sell red coloured standard bulbs anywhere?

D-Rider · #2 Post by **D-Rider** » Tue Aug 28, 2007 9:30 pm

Goldie Posted up about this today too

LINK

As I said there, failing LEDs are very surprising - sounds like some poor design.

Goldie · #3 Post by **Goldie** » Tue Aug 28, 2007 9:36 pm

I was going to say yes but someone did it for me!!

D-Rider · #4 Post by **D-Rider** » Tue Aug 28, 2007 9:41 pm

Sorry

FlyingKiwi · #5 Post by **FlyingKiwi** » Tue Aug 28, 2007 9:52 pm

Hi guys.
I got a pair of 24 (18 back, 6 sideways) LEDs from Bulbs R Us on ebay for £9.50 delivered.
fitted them back at the end of May and have done about 3500miles since and no probs.

HowardQ · #6 Post by **HowardQ** » Tue Aug 28, 2007 9:59 pm

That's cheered me up, they were the ones I ordered first but didn't get!
Still worry though, when 3 different lots have failed so quickly, hardly a one-off.

falcomunky · #7 Post by **falcomunky** » Wed Aug 29, 2007 5:41 am

My brake lights failed on mine after less than a thousand miles. Though I suspect thats more to do with my front clappers and brake lever being slightly seized on fer about 500 of those 1000...

Firestarter · #8 Post by **Firestarter** » Wed Aug 29, 2007 7:35 am

Had two sets, both off of ebay - the first set "worked", but didn't connect right in the bulb holder, so they would light but wouldn't get brighter when the brake light was pulled

. Wired them up with flying leads and they were fine, poor quality control on the bulb bases, I guess.

Second set seem to be spot on, but had to wait a fortnight while they were dispatched from China! They are really bright, think they're 18 back/6 sideways, so light up the reflector pretty well.

Guess it's just luck of the draw, going to try and mod the original bulbs to get a better contact, but at the moment the others are doing fine.

Falcopops · #9 Post by **Falcopops** » Wed Aug 29, 2007 8:24 am

I had a similar problem a ways back, but with the running light not the brake.

Prised up the contacts in the housing a bit and seemed to make a difference for a while, but not for long. I reckon it was a bad batch.

Fausto · #10 Post by **Fausto** » Wed Aug 29, 2007 3:21 pm

I've had no problems yet (That's done it

). Can't remember where I got mine - probably Ebay. They are the sort with rear/sideways facing leds though. I wouldn't be happy with the straightforward front only facing bulbs as you do need that extra light from the reflector IMHO.

Howard, did you test the 'failed' bulbs with a direct 12v supply?

EDIT - sorry, just read the parallel thread and most of this is irrelevant

D-Rider · #11 Post by **D-Rider** » Wed Aug 29, 2007 3:41 pm

Fausto wrote: I wouldn't be happy with the straightforward front only facing bulbs as you do need that extra light from the reflector IMHO.

Not sure I understand the reasoning here.
A normal bulb requires a reflector because it chucks out light in all directions (well not along the axis of the filament but you know what I mean). The reflector redirects the light that started out travelling towards the front of the bike to emit it from the rear.

The LEDs have a much narrower cone of emission and throw almost all of the light out in a cone. If the light is naturally shining out of the back, why would you then want to shine some of it in a different direction to then use a reflector to get it to shine out of the back?

Now I can see an argument to have some LEDs facing sideways but this has nothing to do with reflectors.
Due to the narrow(ish) cone of light emission, I was concerned that you may not see the tail lights from the side of the bike - so I assumed that sideways facing LEDs may be necessary.
However I'm one of the lucky ones that has a set of Nooj's LED tail lights (tough luck if you haven't got them as Nooj has stopped making them). All the LEDs point directly backwards and the circuit boards they sit on completely cover the reflectors. With the Red lenses they were megga bright. With the filtering of the smoked lenses, they are not quite as bright but I think still brighter than standard. The thing I have noticed is that you can see the tail lights from the side. My guess is that this is probably due to the tail lens acting as a diffuser. Whatever the reason, it seems to work.

Fausto · #12 Post by **Fausto** » Wed Aug 29, 2007 4:11 pm

D-Rider wrote:
Fausto wrote: I wouldn't be happy with the straightforward front only facing bulbs as you do need that extra light from the reflector IMHO.
Not sure I understand the reasoning here.
A normal bulb requires a reflector because it chucks out light in all directions (well not along the axis of the filament but you know what I mean). The reflector redirects the light that started out travelling towards the front of the bike to emit it from the rear.

The LEDs have a much narrower cone of emission and throw almost all of the light out in a cone. If the light is naturally shining out of the back, why would you then want to shine some of it in a different direction to then use a reflector to get it to shine out of the back?

Now I can see an argument to have some LEDs facing sideways but this has nothing to do with reflectors.
Due to the narrow(ish) cone of light emission, I was concerned that you may not see the tail lights from the side of the bike - so I assumed that sideways facing LEDs may be necessary.
However I'm one of the lucky ones that has a set of Nooj's LED tail lights (tough luck if you haven't got them as Nooj has stopped making them). All the LEDs point directly backwards and the circuit boards they sit on completely cover the reflectors. With the Red lenses they were megga bright. With the filtering of the smoked lenses, they are not quite as bright but I think still brighter than standard. The thing I have noticed is that you can see the tail lights from the side. My guess is that this is probably due to the tail lens acting as a diffuser. Whatever the reason, it seems to work.

Well when I tried a unidirectional led bulb it was bright, yes, but only in a small concentrated spot. With an multidirectional led bulb you get the bright concentrated spot as well as extra light thrown out from the reflector 'filling' the lens as it was designed. I have no idea if there is any difference in brightness but feel more visible with a 'larger' light at thr rear.

D-R, try masking off all but 2 10pence sized spots on your posh light board and see what you think

Firestarter · #13 Post by **Firestarter** » Wed Aug 29, 2007 6:46 pm

Fausto wrote: Well when I tried a unidirectional led bulb it was bright, yes, but only in a small concentrated spot. With an multidirectional led bulb you get the bright concentrated spot as well as extra light thrown out from the reflector 'filling' the lens as it was designed. I have no idea if there is any difference in brightness but feel more visible with a 'larger' light at thr rear.

Think I mentioned this in an earlier thread, I followed Falken just after he'd fitted his clear lens and LED's, and yes, they were very bright, but also focused - easy to miss especially in daylight. The sideways LED's off the reflector give a much wider field of emitted light, so it's more likely to be seen.

Pierre · #14 Post by **Pierre** » Wed Aug 29, 2007 9:16 pm

I soldered extra lumps onto the errrr solder lumps on the base of the led's as i found the extra weight of them over standard bulbs made them droop.

And your right about the direction of led's. I have bare bulbs sticking out the back at about 20degrees and the new bulbs are very feignt in daylight and hardly get brighter when braking. But looking at them straight on, they are mega bright.

My first leds were opaque and were great - lit up the whole led not just the tip - till they vibrated out, but the 2nd ones are clear and probably have a viewing angle of 5degrees

HowardQ · #15 Post by **HowardQ** » Wed Aug 29, 2007 10:48 pm

Fausto wrote: Well when I tried a unidirectional led bulb it was bright, yes, but only in a small concentrated spot. With an multidirectional led bulb you get the bright concentrated spot as well as extra light thrown out from the reflector 'filling' the lens as it was designed. I have no idea if there is any difference in brightness but feel more visible with a 'larger' light at thr rear.

D-R, try masking off all but 2 10pence sized spots on your posh light board and see what you think

Would agree with Fausto, my first set of 16 rear facing LEDs were not very noticable in daylight, even the small bright (?) central area. The 24 LED rear facing units from Halfords were certainly better.
Can't comment from experience as the ones I ordered didn't materialise, but I still want to try the 24 LED (18 rear 6 side), which I think will be better for two reasons,
(1) they should throw a little more light towards the reflectors, which should light up the main unit bit more be still give a bright central area that can be seen from further away, the main benefit of LEDs.
(2) they should also throw light out to the side, so the rear light can be seen better from the side and at 45 degrees, more like a normal bulb.
As for reliability of LEDs in general, it seems I've not been the only one to have suffered problems, with failures on rear light on first bulb then the stop light on the Halfords unit.
So much for the massive increased life as advertised.

Will try again, and see if I can manage third time lucky. If this next lot fail again within 200 miles,

we'll see!