# K-lite RED rear LED tail light



## ktronik (Dec 23, 2006)

K-lite RED, its a real 'blinder' 

SPECS:

3x XPE red/orange LED
1A Max drive level
37deg frosted optics




























K


----------



## piesoup (Feb 9, 2009)

Thats bright! What about some holes or slots in the sides so the light is seen from the side too. Not all cars take you up the rear!


----------



## ocean breathes salty (Oct 1, 2006)

hang on a second..... is that last photo in a cemetery??? What the hell?


----------



## racerdave (May 12, 2007)

Dude, you should also provide more detailed build, photos, etc. There's a manufacturer's forum for your posts.


----------



## jmitchell13 (Nov 20, 2005)

Does anyone else think that blinding traffic with a 3x XPE light sound like a bad idea?

I'd prefer to see a wide light bar with moving lights or some other unique blinking pattern.


----------



## OverTheHill (Dec 3, 2004)

jmitchell13 said:


> Does anyone else think that blinding traffic with a 3x XPE light sound like a bad idea?
> 
> I'd prefer to see a wide light bar with moving lights or some other unique blinking pattern.


+1

I've always been a little bemused as to why you would need a _really_ bright back light. About the only justification for using one I think, is during the day if it's raining.

You can see very cheap red back lights from several hundred metres away at night, especially if they are flashing. Anything brighter just pisses people off especially if you are another cyclist following a bright back light, it can be mesmerising.


----------



## HuffyPuffy (Jun 9, 2008)

jmitchell13 said:


> Does anyone else think that blinding traffic with a 3x XPE light sound like a bad idea?
> 
> I'd prefer to see a wide light bar with moving lights or some other unique blinking pattern.


I was thinking the same, I see spots when I am behind one of those Camry Hybrids with LED tail lights (nice car BTW). I think it has to do with the focus of the LED vs. a diffused light of comparable brightness.


----------



## HEY HEY ITS HENDO (Feb 23, 2008)

jmitchell13 said:


> Does anyone else think that blinding traffic with a 3x XPE light sound like a bad idea?


 ...+1, they are blinding!

...on dark unlit roads especially, .. blinding bright back lights would cause real problems,
example, how many people out there are driving with impaired and reduced night vision?
you dont have to be in your 60`s and 70`s to suffer from age related macular degeneration, diabetic retinopathy etc etc
the last thing you would want to be doing is blinding these people as they approach you at speed!!
come on, reflective tape, blinkies etc are more sensible and effective!
and hey, spare a thought for all us easily pissed off motorcyclists!
fog lights on when it aint foggy
feckin high level led brake lights grrrrr :madman:


----------



## piesoup (Feb 9, 2009)

HEY HEY ITS HENDO said:


> ...+1, they are blinding!
> fog lights on when it aint foggy


You have no idea how much that annoys me!! :madman: :madmax:

Yeah, a hi vis jacket or reflective tape is very effective. 
Like OTH said, a cheap rear light off DX will be much more effective. Plus you could buy a few for the same price. One in your bike, one on your bag and one on your helmet. Sorted.


----------



## ktronik (Dec 23, 2006)

Come on fellas, like any other front bike light you have, you don't go around with your 7up on high on the bike track/ road....

low modes drives @ 80mA across the string & with the frosted optic its not blinding @ all...its the non frosted light, like a clear 5mm/3mm Red that hurts your eyes to look at...

good for rainy days (day time)
good for night time when you want to keep your night vision, red has less impact on this...
good for letting NASA know where you are if you get stuck... :thumbsup: 

K


----------



## Rich_SC (Oct 10, 2009)

I'm using a Magicshine with a red lens on SOS mode...to say this is equivalent to a $5 blinkie is completely insane. I get a LOT more respect with a big tail light and I'm guaranteed to be seen in all conditions...if they're blinded then they won't get that close which is what I want. This setup is so much safer I can't believe it's being argued against. ut:


----------



## zemike (Sep 3, 2007)

A red tail light should be large and it must have side visibility.

How about putting a flashlight diffuser on this one?


----------



## piesoup (Feb 9, 2009)

zemike said:


> A red tail light should be large and it must have side visibility.
> 
> How about putting a flashlight diffuser on this one?


Exactly! You ned a large amount of light, to bee seen from all angles Not a bright single point. 37 degrees isnt that much of a viewing angle. I'm thinking more 270 degrees, ish.



Rich_SC said:


> to say this is equivalent to a $5 blinkie is completely insane.


Where the blinkies do come into their own is that if you have a few flashing on your bike and maybe helmet, you are alot more visable. Infact this morning when dropping the Long Haired General off at work, I saw quite a few cyclists. When they only had one brightish rear light, it was hard to judge how far away they are. Is it a single bright light far away, or is it a dim one close up. Only when my headlights lit him up did I see that infact he was pretty close. On my way home I saw another guy with a couple of rear lights and a reflective bag cover. So much easier to judge distance. The Cateye type or obviously better than a $5 blinkie. Look at them, many LEDs with a WIDE field of view.

Do you really want to blind the driver of a one and a half ton lump of metal coming up behind you?! Red light might not affect your night vision but it can still be too bright to disorientate you.



ktronik said:


> low modes drives @ 80mA across the string & with the frosted optic its not blinding @ all...its the non frosted light, like a clear 5mm/3mm Red that hurts your eyes to look at...


Ahhh, but you only had the NASA beacon in your advert!!


----------



## ireland57 (Sep 11, 2009)

There's nothing wrong with my night vision but I nearly got a bike rider with a $5 blinkie. He was on a road lit by orange lights and was wearing black clothes; I saw him early by accident. 

The light was his saviour but it made me determined to revisit my tail lights. A blinkie is not good enough.

Car taillights are much brighter and are attached to a big hunk of metal sheet to reflect.

KTronic's taillight is a Great idea but I'd personally like to see it a little less dazzling for the other motorists.


----------



## Maximus_XXIV (Jun 7, 2009)

I have a couple of thoughts on this one.mostly cause I think this one was built for me. First is that the light does not need to be set up to shine directly into the eyes of motorists just like you would not set up a headlight to shine into the eyes of motorists. I agree that a diffuser lens is a good idea and I think I may pursue that.

Also, remember that not every commuter shares your commute. In an area with lots of traffic and many competing light sources, it is good to be bright, much like a car or motorcycle tail light. Now add wet roads into the picture and many lights would just get swallowed up into the background.

This light should not be the only one used. I am a huge believer in redundancy in lighting because they will fail. Point this down a bit to add presence and add a few blinkies and drivers will know you they are there and we will hope they are smart enough not to stare directly into the light.

How bright are car tail lights anyway?


----------



## [email protected] (Mar 28, 2007)

There's nothing wrong with a really bright red tail-light if you are considerate. I recently finished a SSR-90 red LED light that kicks out about 750 lumens:










It's dimmable, so I turn it down a bit at night. Where I live out in the boonies, I run it at about 1/3 power in the evenings. At that level folks slow way down and pass me way over in the left lane. I had a local sheriff stop once and tell me he thought I was a UFO. He complemented me on the light and didn't accuse me of being a hazard. When you ride on narrow country roads without a shoulder, you want a tail-light bright enough folks will notice the reflection off snow or vegetation, before they even get around the turn and have you in their line of site, especially since most tend to ignore the 30 mph signs and drive 50 or 60. With a regular blinkie, I fear by the time they saw me I'd be their new hood ornament 

During the day I run it full out using a blink pattern that sort of looks like it may be coming from an emergency vehicle. 3 quick blinks followed by a half second pause and repeat. That gets noticed. It isn't any brighter than sunlight reflecting off a the window of a parked car, but folks pick up on the pattern and slow down. It is unpleasant to stare at from a few feet, but that doesn't happen much (there are 2 stoplights in the entire township I live in).

Mark


----------



## rayhead00 (Oct 29, 2008)

Ktonic and Mchahn... I like it! My perfect commuter tail light would be that bright, but I also think that it needs to have some additional side viewablity and at least one of the leds need to blink.

I like the way you guys thought out the different modes for many situations; especially the brighter/blinking day time mode.

What kind of run time are you all getting?

Has anyone toyed with combining a flashing led and a continuous led in one unit?


----------



## ifor (Apr 15, 2008)

*another bright tail light.*

My homemade taillight has 2 leds that can run at up to 500ma each and there are a host of flashing and steady options avalible. I normaly just run an alternating patern with the power down at about 100ma lower if I am with other people as that is a bit bright if you are right behind it. In fog in daylight I will turn it up a bit.










I am using a flare optic on one of the leds which gets it good and visable from the side. The diffuse spot on the other means you can still be seen well from 200m+ back by fast aproching traffic.

Here is a beamshot with the setting I would typicaly use in the day.










More pics


----------



## [email protected] (Mar 28, 2007)

Looks nice ifor. I am impressed that you manage to cram batteries inside as well as the driver. What size tubing is it? Looks like 1.25 or maybe 1.5 inch square.

If you want a more finished looking endcap, check out places like Mocap for things like: http://www.mocap.com/plastic-caps-square-vinyl.html , they fit on near water-tight yet are pretty easy to remove. Mocap likes to give out free samples, just don't get too greedy. They probably won't work for your current build, but think about them for the next one.

What did you use for a holder? Is that a stock headlight holder you pulled off another light?

You must be using some kind of boost driver. Did you design it yourself? Or are you using a DX or KD driver?

I like the look of the flare lens. I may have to try somethink like that on my next SST-90 build.

Mark


----------



## ifor (Apr 15, 2008)

It's bigger than it looks 40*40*75 and not light at 220g. If I was doing it again I would not have it all Alu but just have the plate with the leds metal and the rest plastic. It is wide enough for 2AAs in a holder then the driver takes up about the same space.

The mount is off an old comercial tail light. I have had to add a second one as with just the one and being so heavy it would not stay still.

Driver is base off this thread  tweaked for two instances and all the code re-writen in C . It's just a linear type driver but 2 rechargable AAs 2.4v and red leds with a vf of about 2.1v at a high curent make it a very good match. I have used it a few times as it also works well with a single li-ion cell and one or two leds in parallel, having the ability to reprogram it is good and I get lots of levels which I like.

I Just used it in a realy light weight running headlight which will also be my emergancy spair when biking. 2 XPGs and a single 14500 cell at 100g. Having the driver in the light head I have managed to add thermal managment which with somthing that light is a nice thing to add.









The endcaps look good I will have to try and get hold of some.


----------



## znomit (Dec 27, 2007)

Anyone for ping pong?


----------



## ktronik (Dec 23, 2006)

Get out, that's super cool!!... looks like the back half of a k-lite, but what's the red?? XPE triple??

K


----------



## znomit (Dec 27, 2007)

ktronik said:


> Get out, that's super cool!!... looks like the back half of a k-lite, but what's the red?? XPE triple??
> 
> K


Just a crappy red emitter from Jaycar. Half as bright as my crappy XR crees so I'd like to see what a triple XPE does. 
No optic. The ball illuminated completely uniformly, looks really cool.

The ball will fit nicely down into the fins (just sitting on the super smooth threads here).
:thumbsup:

_ps
Complete bugger to photograph, the red saturated. Had to wind the current way down. _


----------



## ktronik (Dec 23, 2006)

znomit said:


> Just a crappy red emitter from Jaycar. Half as bright as my crappy XR crees so I'd like to see what a triple XPE does.
> No optic. The ball illuminated completely uniformly, looks really cool.
> 
> The ball will fit nicely down into the fins (just sitting on the super smooth threads here).
> ...


Oh really!!... HHmm you got the patent yet??... if its cool I might try one... :thumbsup:

Another first for the Kiwi's!!! Right on BRO!!



K


----------



## znomit (Dec 27, 2007)

If I was going to sell them I would have put up this picture


----------



## ktronik (Dec 23, 2006)

znomit said:


> If I was going to sell them I would have put up this picture


Yes I see, some how you have harnessed the SUN!!!

K


----------



## methods (Apr 7, 2009)

Nice - I like the idea of shining the light down slightly so that it splashes across the road at night - especially in the rain - that will create a nice "keep out" zone. 

There wont be any blinding issues if the light is not aimed directly at motorists.

-methods


----------



## znomit (Dec 27, 2007)

*The little guys came over to play*

Cranked it up to 500mA and sat next to Mars4, PBSF, LD1100, LD600.
Side on no competition. Though front on its a different story. Needs a rear window and optic.


----------



## Itess (Feb 22, 2009)

znomit said:


> Anyone for ping pong?


That's really good idea! Now I need to build a rear light also


----------



## [email protected] (Mar 28, 2007)

Ping Bong anyone? Err I mean Ping Pong.

Like the light. The ping pong ball actually makes the whole thing visible from over 180 degrees. I wonder how much light you lose because of the ball?

Hey Ktronic, I was just reading in the XPE data sheet that the max drive current for red or red-orange XPEs is 700 mA. If you're runnin' 'em at a full amp you're likely to limit their lifetime. Do you have any kind of thermal control on your driver setup? Otherwise, you'd better ride real fast 

Thought I'd do a bit of thread hijacking and show a few pix of tail lights I have built.

Front view of the "Easy DIY style Tail Light":










The left lens is an oval and the right is a wide beam. This was an early experiment. Most of the ones I've built lately have used the regular wide beam lens.

The hole in the top is a rivet nut. Drill a hole for the nut before installing the LEDs or doing any gluing. Once you have everything in place except maybe the driver, put the nut in. It's threaded to accept a standard bolt, so now you have a nice place to mount your tail light.

View of case and driver:










It's a custom made driver I designed. It slides right into the pcb boards slots in the case, which is the same Hammond case used in the Easy DIY light: https://forums.mtbr.com/showthread.php?t=407160

Here's how I mounted the LEDs and lenses:










You cut a piece of 90 degree angle to be the LED base and then glue it to the Hammond case (use AA). Glue the LEDs to the base with Artica Alumina (AA). Then I seal all around the edges with hot melt glue. I use some electronic grade stuff, but since you never get any glue on the LEDs or wiring (hopefully  ) you can probably use any kind you want. Then just set the lenses over the domes of the LEDs. And finally inject some epoxy into the area you sealed with hot melt glue. If you don't seal the area with glue, the epoxy leaks around the edges and makes a mess of the back compartment of the light. The epoxy bonds the lenses in place, you only use a little, so you don't mess up the optics too badly. It helps to use epoxy that comes in a mixing syringe, like this from devcon: https://www2.acehardwareoutlet.com/(p2jfiqf3z23vrf55p4nb2uet)/ProductDetails.aspx?SKU=998041246. I like the 5 minute stuff. The 30 minute stuff may be stronger. The 60 second stuff gets real hot when it cures, I'd stay away from it. Wear disposable gloves when using epoxy and work in a well ventilated space. Keep some rubbing alcohol and paper towels to wipe up any spilled epoxy. You also need someplace warm. The stuff doesn't flow well below about 50 F.

The technically astute will notice the LEDs in the above picture are actually green K2 LEDs. This picture was taken while making a green LED light for a Christmas ride my local Mountain Bike Club ( https://www.fatsinthecats.com/ ) does a couple weeks before Christmas. I usually use Luxeon III Red-Orange LEDs. At 1.5 amps you get around 190 Lumens out of each emitter, or a eye frying 380 lumens from both. Not quite the same power as the 750 lumen beast I showed a beamshot of earlier, not as bright than Ktronic's Red K-Lite, but still respectable. These are the brightest red LEDs I've found in a single emitter. Lumileds decided, for some boneheaded reason, to stop making them.

Lumileds recommends using read-orange rebels as a replacement. Here's a prototype rebel tail light I built:










Same idea as the Easy DIY, but I used some anodized rectangular aluminum tubing for the case, and found some plastic endcaps that fit it perfectly. Since I sealed around the lenses with epoxy, I decided to not bother with any front plastic cover. The lenses are some wide angle ones from Deal Extreme. I like the wide beam ripple lenses better.

It's a pretty bright tail light, but not as bright as the Luxeon IIIs. The IIIs will go out of production in February, so order 'em now if you want to build a tail light.

Mark


----------

