Giro

I ordered the much discussed red LED Ultrafire WF-501B Philips Luxeon K2 flashlight on June 20 from DealExtreme. On July 9 ordered the Cree XLamp XP-C-R2 5-mode 90 lumen red LED drop-in module (thanks to BertieB for posting it was available). The Cree drop in works and now I have a rapidly flashing tail light (about 8 to 10 Hz, similar to the strobe flash rate of a Fenix L2D).

The details:
Forewarned of DX's erratic quality control, I was disappointed but not surprised when I first turned the stock WF-501B on to find it had 1 mode, "ON" and "ON". One of the ON modes was a bit erratic so I suspected a short and per a thread on Candlepower forums I knew metal chips or swarf from machining were not always cleaned out (also sometimes bad soldering). I completely unscrewed the light into its five major sub-assemblies and spotted a small sliver of metal inside the tailcap (part with the switch) that looked to bridge across the contacts. After carefully removing it with some fine needle-nose pliers, the light had both an ON and OFF mode. Impressively bright, as others have posted.

I prefer at least some of my rear lights to flash, ideally the distinctive PB Superflash's or some of the Dinotte taillight's modes. When BertieB posted about the Cree drop-in with a flashing mode, I boldly ordered it.

It arrived today and appears to be an almost identical reflector and brass threaded module end to the WF-501B's stock module with a different LED and circuit board (more on those later). Unscrewed the stock module, screwed in the Cree module, and it worked. Beam shape very similar to stock, about as bright (maybe a tad brighter).

There are some differences in the mounting of the LED to the PC board. The stock module I got has some hard white glue beneath and extending out from under the LED (see photo) Anyone know if this might be thermally conductive epoxy?

In contrast, the Cree drop-in does not have anything extending out from underneath but is very close to the PC board. (see photo). I'm uncertain if it actually touches the board but I could not slip any of some 0.003" plastic film underneath the LED. Any comments on this heat-sinking vs. the stock?

The Cree reflector also has a white plastic ring on the back where it could contact the leads from the LED (see photo).

Finally the beam shots.

Coming attraction: Outdoor beam shots at distance with comparison to the Dinotte 140R-AA-R Taillight.

weavers

can you post a short video of the different modes the cree xlamp offers?

lutz

Thanks for the great info !!!

Chris_in_Miami

Thanks for being a pioneer, my order is in!

calbrner

buying the drop in gives a flash mode? that's the only difference?

znomit

The white stuff is thermal epoxy of some kind. The cree is reflow soldered to the white "star" board below it, this board will likely have thermal epoxy under it.

lutz

If possible could you also relate your run-time experiences with the drop-in module?

Chris_in_Miami

That's the only reason I want it, the flash is more attention-getting IMHO. The WF501B would be ideal for me if it had fast and slow flash modes coupled with a full power mode. The drop in is a compromise, but I'll give it a shot.

I have the ability to do the soldering for a DIY unit, but I haven't done the research on which driver to use. If anyone has a suggestion on which one would work with this light, I might have to break out the soldering iron.

Giro

Took quite a while before I had a good night to shoot my amateurish video plus lots of help from the household computer expert to get the raw Quicktime video to something we could then edit out several minutes of inactivity and add the titles, but here it is. I only recorded the flashing mode of the Ultrafire+Cree and my favorite flash mode of the DiNotte.

LINK

As I note in the YouTube description, due to the limitations of my video recording to duplicate the wide range of illumination your eyes detect, both lights look much dimmer in the video than you would perceive them. Both are quite bright.

I should have also taken a rear view video of both, but did not think of it at the time.

bourmb

I bought this red LED dropin for my Solarforce L2. They state it is rated at 150 lumen, and it is bright as hell! The only downside it is single mode. Does anyone know where I could purchase as circuit board with a high strobe feature?

https://cgi.ebay.com/Spiderfire-CREE-...d=p3286.c0.m14

lutz

Thanks a lot for the video !!!

Giro

Here is the Ultrafire WF-501B with the Cree drop-in on high vs DiNotte 140L-AA-R on high in side-by-side ceiling beamshots in response to a YouTube question regarding which is better.

Good question but no simple answer. The Ultrafire's deep reflector gives a fairly narrow very bright beam with nice spill outside the central beam. The DiNotte is the opposite; it has a very shallow reflector and stepped-type lens resulting in a relatively broad even beam than is not as bright in the center. In flashlight terminology, the Ultrafire is a "thrower" while the DiNotte is "floody".

Which is better? It depends. If you want to be seen from a greater distance in back of your bicycle, for example riding at night on a relatively straight, high speed road with few intersections, I think the Ultrafire is a bit better (with the flashing/strobe Cree drop-in). On the other hand, if you are in lower speed limit residential streets with lots of intersections, the DiNotte may be better because of its wider beam. On a dollar basis, once you have invested in the 18650 batteries and a good charger, you could buy several Ultrafires and get about as wide and bright a beam as you want versus a DiNotte or two.

My impression is the total lumens of the two lights are roughly equal but you would need an integrating sphere to sum up all the light from all the angles to really tell.

I provide two exposures because one picture from any camera is incapable of recording the wide range of light intensity that your eyes can perceive. Even these two, one with a fourth the exposue of the other, do not represent what they look like; both beams are entirely red but the central beam is so bright that the camera sensors are saturated and record it as "white". Our eyes are capable of perceiving about 12 stops or 2^12 in a scene while a camera records about 5 to 6 stops or only 2^5 or 6. A better technique is to do high dynamic range photography which I may try, but no time for that tonight.

jangul

Thanks. Do you know how to see wich flashlights the drop-in will fit into?

I am trying to find one that uses AAA or AA batteries, as i have plenty of those. And my girlfriend hates all the different chargers I have around...

Like this one: https://www.dealextreme.com/details.dx/sku.26340 ?


And also: How do you mount the flash?

lutz

This might be a good accessory for our flashlight/taillight. A new diffuser from Fenix (AD401):
https://www.fenixlight.com/viewnproduct.asp?id=50
Supposedly $5 on pre-order.

EDIT:
It will not fit the Ultrafire. The diffuser diameter is too small!

bourmb

Wouldn't some frosted Scotch tape do the same?

lutz

I had a cygolite frontlight previously which came with a clear plastic diffuser. It did not diffuse a lot, but compared to scotch tape the light certainly remained brighter.

weavers

i love all the hard work you guys put into making these post. i bought a WF-501 and i think its great running soild. i would love to run two, one solid and one flashing. i just don't like the rapid strobe. i'd perfer flash 2-3 times and rest then flash again. i think strobe is to much for drivers. i think an sos mode would be even worst, cops might pull me over. so right now i have the 501 paired with a PBSF, not sure if the superflash is bright enough to be seen effectivly when its 12 inchs apart

SSSTANG

I ride rain-or-shine. Is the Ultrafire WF-501B waterproof?

Cyclist0107

The Ultrafire does have O-rings. I would suspect that in rain it should keep dry. I have not had any issues with mine, in light rain and drizzle.

Chris_in_Miami

Mine came in earlier in the week. The rear o-ring snapped when I removed the tail cap and it doesn't appear to have been lubed, the front one did the same. No big deal, I can replace them easily enough. I cleaned up the trademark DX machining swarf, popped in a battery, and WOW is this thing bright!

The drop-in module seems just as bright to my uncalibrated eyes, but with the all-important flash mode. For what it's worth, I have two other strobe-mode flashlights from DX, the Ultrafire U4-MCU and the Ultrafire C1 R2-WC. The drop-in module's strobe rate is a tiny bit faster than the U4-MCU, but quite a bit slower than the R2-WC. It's pretty attention getting, but I'd be thrilled if it had a slow strobe rate option.

Now for the bad: the light stopped working within an hour of use, as I was tinkering with the two LED modules. It turns out that the tail switch went bad within a few dozen cycles. Again, not a major issue since I've decided to mount the drop-in module in a custom housing. This is the first problem I've had with a DX order, but I understand that the quality control is spotty.

In the end, it's my opinion that the WF-501b is a decent light and an amazing bargain at $9.90, but the XP-C-R2 is an even better starting point for a monster DIY tail light. Hope this info is helpful.

Giro

Thank you for an interesting find. Am I the only one that thinks it looks like a minature toilet seat?

johnny0

i made my own diffuser out of an empty Sephora sample container. It's taped to the front with electrical tape. Here's its compared to a PB superflash. Works really well except i dont know how to attach the light to my bike securely.

SlimAgainSoon

Any other red lights available since this last post?

I managed to lose my Ultrafire this morning and will need a replacement.

Gotta be current, you know.

fiataccompli

stirring up an old thread here....Giro directed me here & I picked up (er...ordered & waited & waited & waited....lol) a WF-501B & the Cree drop-in. OK...the drop in is brighter for sure, but I get no strobe...just two modes of light. I was wondering if anyone has ordered one of these lately...maybe the spec on the drop in has been changed? It has two 'on' modes apparently....bright & brighter and it alternates between the two. Just wondering if there's something simple I should look at in the switch or in the drop-in or if it's just gonna be this way. Worse things could happen than having a steady very bright read beam for a tail light...I've got plenty of lights that blink, so I was thinking that a steady light may be better anyway. Just comparing notes here & thanks for the info. Whatever the case, I'm not gonna bother with postage & the hassle for something so cheap to buy in the first place (and that functions anyway).

Cyclist0383

DX is famous for changing specs without telling their customers.