“REVIEW”: On The Road Z821 - Zoomable – 1x18650 – 940 lumens [Pic Heavy]

@ Anthony Nguyenn

In the name of flashlight science :nerd_face: :student:

The example I gave:


Mine came with group A default (4 L-H modes w/ hidden strobe, memory enabled)

Bypassed tail measurements:

Sanyo NCR18650GA 3500mAh

UL = 13mA
L = 265mA
M = 732mA
H = 2.60A

Feel free to add to review if you want.

My initial impressions with just a few minutes of handling:

The size is awesome, nice and compact!
Anodizing and machining very good.
Focus appears to be good.
Host warms up quick which tells me thermal path between pill and body is good.
The packaging is very good and everything is sealed as if this light is sold in retail stores. (maybe some Chinese REI type place?)

Given how compact the host is I will have to temper how far I will hot rod this light. I dont think it’s suitable for maxing out a 2mm2 white flat but maybe ~5A is good enough. The springs will have to go when it’s modded, they are quite thin.

Assuming mods go as planned this appears to be a very good 18650 zoom light. Granted it’s a huge leap in price from typical shit zoomies it seems to at least be a huge leap in quality above them too.

Shipping time to US: ordered, 30 June, arrived 15 Aug. I guess Singapore > US transit still a bit slow.

I’m not proud of this soldering and it’s only temporary until I change the driver but I wanted to see what i’m in for. They barely left enough LED wire to even account for the extra 0.5mm MCPCB thickness :person_facepalming:

It goes from about ~15kcd to ~39kcd keeping stock driver and putting 3030 2mm^2 white flat (CSLPM1). I used a 3030 gasket I think I got from intl-outdoor long ago and it’s a perfect fit.

To be continued

contactcr thank you very much for your input on the tail current measurements! I am on the phone, so it will be easier for me to edit post#1 in the computer!

Also, thanks for showing your mod-in-progress! That leap on candela is quite wow, just with the stock driver. I assume a different one will make it rise even more, be it at 5A or more!

BTW, did you have and issue with the MCPCB height vs the “reflector” and the contacts with the solder, or do they stay out of contact?

Also, unless your driver is different from mine, the UI should have Strobe / Beacon / SOS as special modes with 2, 3 or 4 multiple clicks from ON. I wish memory could be configured to stay off… :weary:

Again, thank you very much for sharing your words, mods and measurements :wink: :slight_smile: :+1:
And show us the rest meanwhile :wink:

I’m using a plastic centering ring so its probably half or 1 thread less screwed on but still putting pressure on whole pcb by way of that gasket. Not sure how close it is but I had no problems. For the final assembly I may use kapton tape or may not…

Mine has strobe via double click but came default as the 4 normal modes.

Hard to tell if the .5mm from pcb effects focus or not. It’s pretty defined but this LED has very even die so you can’t look for dots or bond wires to be sure

For me, it’s not really modding unless you break something, so here is tonight’s sacrifice:

I thought I could pry the board out first. Nope (well yes, but not recommended) it’s soldered on the other side of the press fit ring.

Oh well, I took apart a perfectly good modded S2+ to gut the driver and MCPCB. I planned to do it anyways but still I hate taking working lights apart cause more than once I just end up with two not functioning lights. Desperate times since LED4Power is on hiatus.

Filed down and pressed into ring, lightly soldered. Ring then pressed into pill, no solder:

Might as well get that tail spring too:

Gotta have that temp sensor. Sad part is I re-flowed the LED cause I feel more confident doing that (on a 3535 board no less) than transferring the NTC from board to board.

Gasket with side clipped, pretty sure from intl-outdoor. It’s probably not ideal cause the “reflector” (MascaratumB’s word) only screws down about half way. Ideally it would be sanded down some.

Tail wont go on, springs are too long, ugh. Button maybe?

Nope, not enough. Tail has to change too:

It turns out this tail is partly why the light is so compact. The tail legos with an S2+ and if you hold them side by side you can see a few mm difference. This light will likely never fit anything but flat tops. It also explains why I initially thought the original springs were so thin and cheap because they have to fully compress to fit a normal battery.

End result:

I set the driver to around 5.3A and measured 63.4kcd

If OTR is lisenting: add another ~1.5 - 2.0mm to the tail cap and get better springs on both ends.

MascaratumB & Contactcr

Very thorough review and nice mod :+1:

So 63 kcd means that it should be close or hit 100 kcd with WF1… That is good result for such light. It could be better(up to 20%) though if they will ever redesign aspheric lens (larger aspherical surface and smaller lens edge, and current is small aspherical surface and too much of “edge” on aspheric glass) .

Yes this is very rare China light that is usable out of a box(nothing special) but it demands modding for wow effect.
It is bit to expensive IMHO for factory version. But if they will ever learn to properly make the light(not just OTR, most China manufacturers) and that means if you are saving on emitter at least put freaking DTP board into the pill!(why they want to save 0,5$ on DTP board?)

This light should be ofered as a host, and it should not cost more than 15$(even that would be bit to much).

@ contactcr
Thanks again for your input on the modding process :wink:
About the centering ring, that also happens with me on the i3, the “reflector” (IDK how its is called, sorry) doesn’t screw all the way down :zipper_mouth_face: I didn’t have capton, I used electrical tape, even if nor ideal.

On the mod, did you took the retaining ring of the driver out? It seems that it can be taken out of the pill throught those small holes in the side. I’d like to “maintain” the integrity of the original driver, it can be worth to make another mod :wink:

Normally I don’r solder any temp sensor wire to the led MCPCB :smiley: Am I doing it wrong? :partying_face:
Or does it have to do with the type of driver you have?

I’ll put a L4P driver as well, but normally I don’t add those special temp things (I don’t actually know how to work with that :stuck_out_tongue: ), hence my question.

Quite an improvement since the original measurements. A W1 would probably get some more intensity, but the W2 also seems to project the light far away :wink:
Well done :wink:

And BTW, you did a pretty clean job in the mod, I am very messy with this stuff :person_facepalming:

I may need to start thinking about a new spring for the spring, maybe the original is too thin afterall :weary:

@ luminarium iaculator
Thanks for your words! And I hope you are enjoying your light as well.
BTW, did you see the YAGE zoomie light that is pretty similar (although bigger) than this light on AliExpress? It is sold, the complete light for around 7€. It probably has aluminium pill and acrylic lens, and despite being bigger, it still seems a compact zoomie at a nice price :wink:

BTW, this is that YAGE I mentioned above.
(which is more similar to the old Z821)


I did take the ring out eventually. I think using heat/cool and something small and stiff (stainless something) you can pry ring gradually from either side. If I had to do it again I would do it that way and try to push driver out of ring while it’s on hot plate or something.

It’s not necessary to function. L4P driver has temp sensor on driver and also this NTC connection for supported PCB. The MCPCB temp steps down at 115C or something while driver temp steps down sooner, 65C or whatever custom setting. I think it’s a more accurate way to do step down based on MCPCB temp though.

As for how “clean” everything is here is my tip: old toothbrush + alcohol and just dip toothbrush and scrub anything and everything.

Thanks for both replies contactcr :+1:

I guess taking out the ring will be better then. I know thus is their normal setting , so it will be better than pushing the driver from the top.

Also, thanks for the info on the driver/MCPCB temp sensor. All the lights I have with L4P driver don’t have that wire, it is always based on the driver itself. Maybe I’ll give it a try this time :wink:

Ahah, best tip :wink:
But I was also complimenting your solder skills. My wire soldering to the MCPCB, driver and spring can become quite nasty, that not even a toothbrush can clean it well :stuck_out_tongue:

Thanks again for sharing this!

If you try temp sensor make sure mcpcb is populated with that tiny resistor at bottom or else it won’t work

Sure, I will ask led4power to send it with the resistor when he opens the store again :wink:

You mean on Hawkeye Focusing Fighting tactics light :laughing: They do exaggerate in description and I can bet they have hollow aluminium pill ass seen on plenty of models plus clasicc non anodized threads with crappy no name press fit switch (you know those white plastic switches with brass cover for spring?)

But maybe I am wrong…

No matter for pros and cons OTR Z821 is one of the best commercial available 1x18650 zoomie in a world. But still can’t you tell to OTR that it would would be quite fair that they put Osram White Flat inside with DTP board? That way 30$ price would be approved.
Lead group buy for OTR Z821 with mentioned ingredients and I am sure you’ll collect 500+ buyers in no time…

Hum, I’d be very surprised if you weren’t wrong about that :smiley: That is one of the reasons why this OTR stands out, even in “comparable” flashlights :stuck_out_tongue: It is not funny to mod one of those press fit switches :zipper_mouth_face:

Nor to add a shelf to the hollow pill :smiley:

I guess I’ve said in the Zooming Model list thread why I will not run a GB !
Please don’t get me wrong, but I guess that till now we’ve seen that OTR has a specific market (China), and normally they have very “specific choices” in what concerns leds. XML2 / XP-G2 has been their longtime preference.

The change in user interface, adding configurability, may be an opening in perspectives, but I am not sure how open they would be to invest in new Leds. Maybe I’m wrong this time.

Also, communication is sometimes not as “fast and clear” as needed to do a GB.

More than that, I know that besides that led, people would start begging for “this and that”, with W1 or W2, package or no package, and… I honestly don’t have the time or patience to negotiate endlessly. I do appreciate the work, time and effort that people running GBs and BLF projects have to make things “real”!

BTW, “this is the only ”pseudo-GB”“:[Group Buy] ***RovyVon Angel Eyes E300S*** - *[Discount: 20% /+50 Units = 25%]* ___CLOSED___ that I ever ran here on BLF. It is sure that other things got in the way by that time, but I’m not tailored for that kind of organization.

OK… But for that price it should at least have DTP MCPCB :person_facepalming:

Yes I had such results so in fact that is moonlight, ultra low, low and high… Middle mode is missing as I said in mine small review about month ago here. It should have middle mode at 1.8A current draw.

I will ask them if there is any possibility to have some of the changes suggested, be it the DTP or even the Osram :wink: But, I wouldn’t count with too much opening for that on their side.

About the data, sorry, I forgot you had measured it before :person_facepalming:
I linked your post above on the review, but I didn’t pay attention to the measurements.

Well, with the numbers, it becomes more obvious that the distance between medium and high is less “visible” than at sight (eyes, in this case). I believe they don’t want to push it “too much” to allow better runtimes, but it sacrifices some output :zipper_mouth_face:

BTW, yesterday I modded the Z821.

Like contactcr, I dismantled my Convoy S2 that had a led4power 4A-6A driver and Osram White 2 and put it in the Z821 :partying_face:
Whaaaat?!! I couldn’t wait till led4power reopens the store :stuck_out_tongue: :smiley:

I also replaced the tailswitch, for a forward clicky switch. I used the PCB & spring of the OTR M1 and soldered a FC switch bought from Simon. Tailcap is orange and fits better in colour.

I also added a screw-in pocket clip, that I “torched” a little bit to be more suitable in colour :wink:

On the head, I blackened the “reflector”, and as I didn’t have any suitable gasket, I added electrical tape and also GITD tape around the led to avoid contact between the solder and reflector, and also to avoid a ring around the led (every gasket I had was creating that).
Still, despite this, there are still artifacts…

I must warn that: I like the throw and output with the W2, but I guess I will replace it for a W1 later, because the rectangular shaped beam seems a bit awkward, at least indoor.
Also, I had to change the driver to CC instead of DD (even at 4A) because with a full battery the highest level was turning into BLUE :open_mouth: CC solved the issue, so beware of the configuration you use in this light!

Some photos below.

Hmm yours is turning blue with constant current set to >4A?

It was, on Direct Drive and fully charged battery (literally taken out of the charger).
Can it be some problem with my setting?

Oh with direct drive I am not surprised. I misread your post as anything above 4A turns blue.

Did you take any measurement of throw or try higher CC setting like 5A?