We need details! 
. U have a good setup for measuring high amps? Take care of all the high amp issues, like bypasses on the springs, heavy LED wires, good wires between the stock driver and LD-1 piggybacked? Low resistance, high amp battery? Fully charged battery?
I would expect at least 4.5A form the LD-1 in a Y3 with all the details taken care of...
At least it’s what I think it is, in my L4 there is now pwm detectable, via ears and eyes. Don’t have an oszilloscope on my desk sadly.
The inducotor is rather small so I assumed it’s a proper switching driver. But wouldn’t write that in a rock yet.
Yeah that’s how preferences differ from one to another, I like the UI somehow but I get your point about on/off.
But gotta say I love this light, it’s just so good to fit your own needs.
Well, its virtualy the same as your setup, its just the emitter is directly wired to the driver with 20 awg
With the same setup i do measure 5.02 amp on my UF c12( with the same driver…
“good wires between the stock driver and LD-1 piggybacked” this might be an issue, i did by best, yet, 3.5 tops
What could i expect from that ld 34?
I realy like how Y3 fits my Ak103, its like its made for that rifle, fits extremely fine
Btw, is there something Y3 similar with a side button and 17mm by default driver? Like hd2010?
LD34 won’t give you any current gain, at least I don’t think it went higher than 3A stock. Just thought it would be good for people like me that are a little annoyed by stock PWM and want to keep 2 cell capability on XM-L2 setup. Some of those LD drivers are able to change current by bridging a set/key pin to ground.
--> I like the MaxToch M12, but no side button 
. Not sure - might be an Olight model out there, but lot more money and I suspect not as good as a modded Y3. Ones I'm familiar with in this size are HD2010, T08, M12 (all tail switch lights). Hhmm, think there's another 2 cell light (longer) out there with a side switch with similar reflector size -- can't recall details... The Courui has maybe an edge on the Y3, but 3 cells would make it heavy, bulky I would think.
Well, even 2 battery ones are too long and bulky(for my taste), Y3 with a single battery and LD 1 would be great if i do manage to fix it as i should: at 3.5amps its better than Olight Sr52, throws better, has tighter beam, its lighter and dont have that fat body
I have to fight it( the y3) obviously!
P.S i didnt had luck with the default driver too, tweaking it brought nothing, from 2amp to max 2.4, tried r100…r050,even r020
Guess you have no pics, but I'd like the details of exactly how you piggybacked the drivers, what gauge wire you used, etc.
From what all I did with mine, I’ve learned that with one cell, you aren’t going to see a DMM register over 2.5 or 2.8 no matter what you do. The voltage sag of the battery above 2A plus the resistance of all the components plus the DMM’s inherent resistance is going to drop the voltage to close to or below the forward voltage of the LED and because the Y3 has a cc buck driver, it won’t pull the amps you want as the V-in has to be above V-out for a buck driver to function properly. It’ll require two cells to get over 3A no matter what you do with the resistors. That’s how mine worked, anyway.
If you’re set on using one cell, you’ll have to swap or piggyback the driver.
As promised… it’s time for some beamshots!
For reference, it’s roughly 30 meters to the shed and roughly 50 meters to two trees at which all the lights are aimed in the middle of the frame.
Control Shot
Nitecore P12
L2M w/ sliced MT-G2 P0 @3A
L2D w/ 3-up XP-Ls @~6A (DD)
Y3 w/ Dedomed Stock XM-L2 @5+A
Y3 w/ MT-G2 Q0 @6A
Mini Maglight LED Pro (… for science.)
And now for a longer shot. Sorry, lots of ambient light around here. Yes, it does actually kinda look like the control shot to the naked eye. No, that is not a creepy werewolf plotting my imminent demise. That’s my dog, Sawyer.
Google says it’s 230 meters to the steeple, and 320 meters to the trees behind and to the right of the steeple from where the light is.
Control Shot
L2D w/ 3-up XP-Ls @6A
Y3 w/ Dedomed Stock XM-L2 @5+A
Y3 w/ MT-G2 Q0 @6A
All beamshots taken with Sony NEX-7 at 10mm (15mm full-frame equivalent), F4, 2.5 seconds, ISO 400, auto white balance.
All in all, the Y3 with the MT-G2 is throwing pretty far considering just how much light and how broad of a beam it’s kicking out. It’s definitely hitting the trees behind the church which are well over 300 yards away. The Y3 with the XM-L2 is throwing much, much further than that. I tried to get the exposure on these as close to reality as possible, and I think they came out fairly accurate, all things (crapton of ambient light) considered.
Let me know what you think. This is now the second time ever I’ve taken beamshots. Pointers for taking better ones always welcome.
The beamshots are good! Thank you. 
Well, from my OP, the Y3 driver I measured just under 23 mm while the LD-34 is listed at 23.6mm - maybe it can be filed/sanded down to fit, but the Y3 driver has two bump outs 90 degs off from the switch, while the LD-34 has only one 180 degs off from the switch, so again, some moddind would be needed.
Not sure why you would want an LD-34 in there, but it may be adoptable - not sure...
i dont want to replace it , i just saw this today and i thought would be a nice alternative if we blow the stock driver.
Well,I bought Y3 from CQG group buy,and I was disappointed,very anemic output and lots of scratches/dents.
Also I couldn't get more than 2Amps,no matter which battery I used.Then,I measured led's Vf and guess what,3.7V at 1.8Amp!
Most crappy xm-l2 I've seen. So,if you use stock led in Y3,it's good idea to check forward voltage,because I'm sure I'm not the only one who got crap grade xm-l2.
2nd,when you use LD-1 in lights with >17mm driver place,it's very important where you solder GND wire on LD-1;best place is closest to sense resistor,or even on sense resistor GND pad(if wire is not too thick).This ensures minimum resistance.Soldering wire on gnd ring that's far away from sense resistor can add significant amount of parasitic resistance,since current must flow through the gnd ring to sense resistor.
what batteries do you suggest ,for use 3x26650 ?
i found this KeepPower 5200mAh 26650 ,if the specs are correct its “small” 6.6 x 2.6 x 2.6 cm ,usually 5000ah batteries are 7+cm lenth
your link goes to the imr this is indeed shorter and 67mm could be right but they are unprotected and no real imr(the discharge curves match the normal 5200mAH cell)
it’s plausible that they are a bit shorter than the normal protected 5200 cells which are 71mm
I have the imr4200(best battery available in terms of voltage under current) with the imr wrapper from gearbest and it is 67.5mm
[quote=led4power]
Yep, the first one that i bought was exacly like that, i had some difficulties with ataching your driver inside but i cleared them
Thanks for the resistor tip, its realy a good advice!
Anyway, i ordered a total of 6 so far, and its my best 26650 side switch host: especialy modded with LD1, when the emitter is dedomed( u2 1A) + efest green 26650 4200ma it both outthrows and outruns Olight Javelot
The last batches from that light came with nearly perfect refelctor, non damaged anodisation and a better driver: at default it pulls 2.8
[quote=Mitko]
Mitko, where have you purchased your latest ones from?