there’s 2 resistors on the board… it’s R150 and R180
you can open up the bezel with rubberized glove, but to access the driver or to change the LED… you don’t need to open up the head… the light came in 4 sections
the head, the driver/LED pill, the battery tube and the tail
Finalyy got the upgrade finished for the most part. Piggybacked the FET based Nanjg to the stripped stock driver because of the mounted e-switch. Lumens: 1,717 @start, 1,656 OTF at 30 secs, 125 kcd throw on a Powerizer, 4.21v, 5.72A tail. Springs copper wired, using 22 gauge wires to the LED, 22 gauge for the + wire from stock to piggyback, 3 24 gauge wires connecting ground between the boards, XM-L2 U2 1A on Noctigon using AS5.
Wow! The PWM value of 1 is pretty incredible - I measure 0.6 lumens. Here's the break down:
PWM Values - Lumens
1 0.6
4 16
16 92
100 663
255 1,656
Issues:
- Thinking the 5.7A is lower than expected - could be the piggybacking with extra resistance, or maybe how I'm wiring the FET, dunno
- an AR lens should help big time
- will re-test with a charged up KK ICR 4000 or 4200
The 5 mode switching is working amazingly:
- no mode memory
- quick click, turns it ON in moonlight (very low moonlight, lower than what you can get with 7135's)
- long quick (hold) of 3/10 of a second turns it on in high
- once ON, quick clicks go up, long clicks (holds) go down
- if you pause after changing modes for more than 1.2 secs, a quick click then will turn the light OFF
I'm finding the .3 secs and 1.2 secs times are working out well for me in this light. Here's the summary:
- From OFF: single click to lowest mode, long click to highest mode
- navigating modes is very easy: click to go from low to higher modes, long click for high to lower modes
- after a pause, single click is OFF
awesome… ! 
The 125k sounds ok but not compared to say a modded 2X or the like. Is the project torch not yet dedomed? - that could jump it to 250-280k?
Right - still with dome, that's why the high lumens #'s, and expect to see that range of throw when de-domed. This light is more a HD2010 replacement/upgrade for the same cost, and for that purpose, it's just about perfect - better quality, e-switch, better throw (a little). I don't see it competing with MaxToch 2 cell lights.
But does the userfriendly mode switch still work?
What mode switch? You mean my customized version? Yes - of course. It's pretty awesome.
I meant the stock white button for changing modes. The big selling point of this light, for me, was the “no worries of it going into any other mode” feature. But no doubt, what you have is even more awesome (please do some beamshots!)
Sure - the whole point was to utilize that switch. The tail switch now is simply is a "lock-out". Everything can be done on the side switch, but nice to have total power cutoff with the tail switch.
Do you have any suggestions for a small, floody e-switch light which could use a similar firmware? (and any extra parts required to get it all working)
I’m hoping to make one which uses an e-switch to control PWM speed in very small increments, to make a variable-speed strobe light. I think a UF-T50 might be a good starting point, but I haven’t figured out where to go from there. (my background is in software, not hardware)
The Small Sun ZY-T29 or ZY-T11 clones. I bought this one: http://www.banggood.com/CREE-XM-L-T6-1800lm-5-Modes-Zoomable-LED-Flashlight-Black-p-80813.html, but received the UltraFire, but it's the same thing. Cheap - I modded it to 3.5A, XM-L2 U2 1A on a Noctigon, with the e-switch custom firmware. The XP-11 at WallBuys.com I've also mod'ed but it's a different setup internally. Check out the T29 and T11 threads for details. The Small Suns have plastic lens reflectors unfortunately, at least at the time, but the UltraFire and Aleto's don't.
It's certainly not a simple mod - ZY-T11/ZY-T29 require to piggyback a Nanjg onto the existing driver because of the switch mounted on the stock driver. For the XP-11, the stock driver can be tossed and replaced with a Nanjg, but wiring in the e-switch can be a challenge, unless you are ok with very fine soldering.
Check post #19 here: https://budgetlightforum.com/t/-/21292
Chris at flashlightlens.com-UCLp_AR just listed a new size I requested for a UCLp: 56.8mm x 2.25 mm, that I requested. He'll basically do any size upon request for the UCLp, not the glass UCL. The stock lens on the Yezl Y3 is 56.8 mm wide and 2.04 mm thick. I'm assuming the 0.21 mm extra width will be ok, specially when swapping out the stock LED for a XM-L2 on copper, because it's slightly thinner. I'll be ordering one to try it out.
Thanks! The ZY-T29 looks really promising. I think I can probably cram an extra board in there, though I’ll want to make sure it’s easy to get at for re-flashing. I don’t recall what extra parts are needed to flash the driver, but I think I saved links for it somewhere.
It has been too long since I got to write any firmware or other low-level code. Hopefully it’ll be reasonably straightforward to mess with the PWM timings to make a good strobe.
… starting a new shopping list now. 
I just ordered one, does anyone have a 26650 battery to recommend?
Also, is the 18650 sleeve (and a battery) that comes with some AAA lights adequate for using in a 26650 light, at least for light (lite) use?
Let me ask something else, if I only intend to use this light to play around for 10 or 15 minutes, and am not in any rush to get into 26650s, will my 3400 panas be enough for my purposes?
The Kong 26650 is a tried-and-true contender. I use it in this light all the time…
Mine didn’t come with the 18650 sleeve, but most others said theirs did. A 3 or 4xAAA configuration should work fine, and at least for a short while, should have not too much worse output since this is a regulated 2.5 amp torch.
I have used a Pana3400 and it’s just great. Just slightly less capacity than the 26650. Same performance as far as I can see.
Thanks for the confirmation on the 18650, and the link to what looks like a good 26650.
Did anybody try to put 4c primaries in this flashlight? Results?
Richard (RMM) has the KK 26650's at competitive prices, plus others, US shipping is fairly cheap. Batteries here: mtnelectronics.com-1865-26650.
4C's? The specs say 3.7v input, and it fits 65cm cells (ie: 18<->650, 26<->650), so don't think they would work.
The protected King Kong at that site is 69.75mm by 26.6mm, will it fit into the light?
Think it should. I got a few protected 26650's of similar size, so could try tonight, if I remember (
). I only use unprotected cells in one cell lights.