Replacement for 5/21W tail light

user11

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Hoping to be able to get some sort of plug and play solution that will make my 5/21W 12V motorbike tail light as bright as it is possible to be. I've seen drop in LED replacements but I'd like to get some expert advice here as I know this technology is always moving forward.

thanks.
 

-Virgil-

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You don't mention what kind of 21/5w bulb you're trying to replace. If it is a P21/5W (with metal base), the only LED version worth trying is this one. Depending on your bike's circuitry and optics, it may or may not work for you.

The best/brightest fully-compatible filament bulb is this one, which produces 553/50 lumens (compared to about 400/38 lumens for the P21/5W)
 

user11

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OK, it's a 1157, there are two in the light fitting and it needs to illuminate the license plate so they either need to be white or red with white at the bottom.

The current bulbs just say 5/21W and they are made in China. The housing on the bike says 32/3CP so I guess that is the same spec as 1157, do you think the incandescent you linked to would be a fair bit brighter?

Would that Phillips Extreme LED have some white on the side to illuminate the tail light? It doesn't say on the packet if it's all red then it won't work.

What do you think about [Link to unsafe/illegal product removed]
 
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-Virgil-

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OK, it's a 1157, there are two in the light fitting and it needs to illuminate the license plate so they either need to be white or red with white at the bottom.

I doubt if you'd have a problem with red light on the license plate, but if you want it white, then use the linked incandescent bulb.

do you think the incandescent you linked to would be a fair bit brighter?

Please re-read post #2 in this thread. It contains actual numbers.

What do you think about [Link to unsafe/illegal product removed]

What do you think "the only LED worth trying is this one" means?
 

user11

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Yeah, I saw the lumen comparison but I don't have a good handle on lumens, I have no idea if they are linear or logarithmic or whatever. Anyhoo, I have ordered the Philips red LED as I can always rig up something else for the license if I need to.

Do you have a lumen comparison for the Philips Vision Xtreme, because I can't find any info about it, thanks.
 

-Virgil-

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Yeah, I saw the lumen comparison but I don't have a good handle on lumens, I have no idea if they are linear or logarithmic or whatever.

Lumens count up just like marbles or grains of sand or sheets of paper: two lumens are twice as much light as one lumen.

Do you have a lumen comparison for the Philips Vision Xtreme

I think that information isn't published.
 

TheIntruder

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Do you have a lumen comparison for the Philips Vision Xtreme, because I can't find any info about it, thanks.

125/24 lm

They've disappeared from most of Philips global sites, so who knows how much longer they'll be available.

Sylvania makes something similar, but they aren't proven. They were about fourteen bucks a few weeks ago, but the price has since gone back up to more normal retail level.
 

user11

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Hang on a minute can someone explain to me how 125/23 lumens is brighter than 400/38 which is the standard bulb? Phillips advertise them at 5 x brighter. I'm pretty confident that they are not going to be 1/3 the brightness of a crappy filament bulb, so where is this discrepancy coming from?

I have tracked them down on the Philips USA site listed under interior lighting http://www.usa.philips.com/c-p/12899RX2/x-tremevision-led-led-signaling-and-interior-lighting it's weird, but there is a picture of the right box and the specifications say 130 lumens without saying if it's the running light or the brake light or if in fact it's not that light at all but on of the interior lights.
 

Alaric Darconville

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Hang on a minute can someone explain to me how 125/23 lumens is brighter than 400/38 which is the standard bulb? Phillips advertise them at 5 x brighter. I'm pretty confident that they are not going to be 1/3 the brightness of a crappy filament bulb, so where is this discrepancy coming from?
They say they're 5x brighter than other LED replacement bulbs. Also, depending on how the light is distributed, a 125lm source can be more effective than a 400lm source. Remember, a filament emits light in nearly 4 pi steradians (almost spherically), the LED device has a narrower emission angle. Sure, the reflector in the lamp will return some/quite a bit/most light from the filament, but the narrower emission angle means a higher luminous exitance.

Also, it produces red directly, all 125lm of it, rather than producing 400lm of white light which then sees a giant portion stripped out by the red lens it's behind.

I have tracked them down on the Philips USA site listed under interior lighting http://www.usa.philips.com/c-p/12899RX2/x-tremevision-led-led-signaling-and-interior-lighting it's weird, but there is a picture of the right box and the specifications say 130 lumens without saying if it's the running light or the brake light or if in fact it's not that light at all but on of the interior lights.
The 130lm will be for the major function (stop/turn), not for the minor function (tail). The website itself seems to fail with showing a festoon bulb with the copy for an 1157 replacement.
 
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user11

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Okie dokie, thanks for the lumen clarification, I'll let you know in a couple of weeks what the verdict is.
 

TheIntruder

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They've proved themselves to be essentially non-functional. This brings us back, once again, to:

Did you even look at link? Apples and oranges.

They're the new Philips Vision-style clones that were released late 2015, not the older "emitter behind a round dome units," which were crap.

Sylvania also released a bunch of Christmas-tree style units as part of the Zevo line overhaul, which probably are crap as well, but these probably work well.
 
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-Virgil-

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Hang on a minute can someone explain to me how 125/23 lumens is brighter than 400/38 which is the standard bulb?

It might help you to understand that the PR21/5W bulb (red version of the P21/5W) produces 105/8 lumens. The filaments are the same as the clear/white P21/5W which produces 440/35 lumens. The difference is purely due to the filter. It doesn't matter whether the filter is in the bulb, over the bulb, or in the taillamp lens; filtering white light to get red results in about this amount of loss. So a red bulb that produces 125/24 lumens (that's what the linked spec sheet says) is going to result in more light than using a white incandescent bulb behind a red filter.

As for "5x brighter", that refers to comparison with the large number of bogus "LED bulbs" on the market.
 

user11

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UPDATE: OK I got the vision LED and it's pretty good, the brake was maybe 15-20% brighter but unfortunately the running light was way to bright thus diminishing the effect of the brake light, so I had to get rid of it. Now I am trying to get the original honda OEM bulb linked to originally but that is proving more difficult that it should be. I am unable to contact the Amazon seller and I am not sure that the bulb for sale in the ad is the one pictured and not a wedge fitting because they have it listed for models of Honda that do indeed take the wedge fitting.

I have contacted three local honda dealerships in Australia and they are unable to locate the part number. One local dealer said they had the original Honda part at $12 each in stock but when I went to pick it up it turned out to be a normal shitty $2 part that they were selling for $4.

So I was wondering if anyone would happen to know who the original manufacturer might be, Philips, Osram, or Stanley? Thanks

edit: I have found this NARVA bulb and I was wondering if it is likely to be as good as the Honda OEM, or even this HELLA brand?

10X Osram Sylvania 7528 P21 5W 12V 21 5W BAY15D Headlight Lamp Automotive Cars | eBay
10 X Narva 12V 21 5W P21 5W Base BAY15D CAR Light Bulbs | eBay
Philips Globe P21 5W 12V 10 Pack 12499STCP | eBay
 
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-Virgil-

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UPDATE: OK I got the vision LED and it's pretty good

The Vision LED, or the Xtreme Vision LED? Two different products; the Xtreme is the one worth trying. The (only) other LED worth trying is this new one from Sylvania which I've seen a lot of good results with.

I am trying to get the original honda OEM bulb linked to originally but that is proving more difficult that it should be. I am unable to contact the Amazon seller and I am not sure that the bulb for sale in the ad is the one pictured and not a wedge fitting because they have it listed for models of Honda that do indeed take the wedge fitting.

For one thing, Amazon's parts application catalogs are a joke. For another, remember that vehicles in one market (such as the USA) often do not take the same bulbs in the same locations as the same-model vehicle in another market (such as Australia). You've got the genuine Honda part number and a link to buy it, so...buy it!

I have contacted three local honda dealerships in Australia and they are unable to locate the part number.

Correct, because that bulb is not used in the Australian market, only in the US and Japanese markets.

So I was wondering if anyone would happen to know who the original manufacturer might be, Philips, Osram, or Stanley?

Stanley.


I have found this NARVA bulb and I was wondering if it is likely to be as good as the Honda OEM, or even this HELLA brand?

No. It's a plain, ordinary P21/5w, just like your bike originally came with. And Hella doesn't make bulbs, they buy them and private-brand them, and quality is inconsistent-to-poor.
 

user11

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OK thanks. Yeah it was the extreme and as I said the beam and the throw were excellent, it's just that the low power was too bright thus diminishing the effect of the brake light. But it was worth a go.

My only other concern is that the bulb is listed as 43/3CP but on the housing of my bike it says 32/3CP what would this discrepancy be seeing as they are both the offset bayonet 12V P21/5W? I am unable to find any information on the 3CP specification.

Anyhoo I've ordered it from Amazon.
 

-Virgil-

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My only other concern is that the bulb is listed as 43/3CP but on the housing of my bike it says 32/3CP

Er...yes, that is exactly what you wanted: a brighter brake light.

I am unable to find any information on the 3CP specification.

What information are you seeking?
 

user11

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Er...yes, that is exactly what you wanted: a brighter brake light.

What information are you seeking?

Well I can understand what 21/5W means, it means what it says, but I presumed that 32/3CP was some sort of other country's code for the same thing but those numbers don't speak of Watts to me. I thought there'd be some sort of conversions chart like you get for bra sizes or shoes, you know, but I was not able to find any.

You speak as if it's plainly obvious that 43 means a brighter brake light than 32, but what are those numbers? are they arbitrary do they have some meaning? Who knows? And the 3CP is the '3' a relative brightness to the 43? or is 3CP code that mean 1157, again who knows?

Is the 43 brighter because it's made differently but is the same Wattage, or does the 43 mean it's a higher Wattage. These are the things I wanted to know but mostly I just wanted to be sure that it would fit.

Moderator Edit
Switching letters around in certain swear words doesn't make it funny or harmless. Please leave that language out of here.

--Alaric D
 
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-Virgil-

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Well I can understand what 21/5W means, it means what it says

Sort of, but not completely. Anyhow, 32/3CP means 32/3 candlepower, which are the nominal bright/dim mode ratings of the American-spec 1157 bulb. The 3496 bulb you have ordered produces 43/3cp, which means the brake light is 34% brighter and the brake/tail intensity ratio is 14.3:1 instead of 10.7:1.

mostly I just wanted to be sure that it would fit.

...because you suspect people on here would tell you to buy a bulb that doesn't...?
 
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