Yezl Y3 - a picture breakdown

You seem to be absolutely right on that one. I added another cell and with three 26650s it did indeed rise up to 4.2A at tailcap.
That should result about 6-7A for the led with reasonble efficiency assumed. :open_mouth:

No, I did not dare to keep it long for a extended period at that current. I’m not too confident about how much overdrive the driver can handle.

Good sport!

If I were you I’d probably target around 4A with my resistor mod (assuming 4A is what you want!). You should be able to do that using just the resistors you’ve got, and it sounds like you’ll probably want to drop the current for your XM-L2 a little too if you’re worried about overcurrent for that driver (6.1A).

That’s just my suggestion though! (EDIT: if you set the actual desired current you don’t have to worry about how many cells you use in the future)

Changing the resistors for a 4-5A max current crossed my mind as well. I think 4A is quite plenty with a MT-G2. For general use that could actually use a low-low mode in addition to the Hi/med/low it has now.

That being sed, I must first give it a quick try outside just to see the huge amount of light it is able to give. :slight_smile:

I’ll keep the XM-L2 as is for the time being. I really like how it throws and I’m not too conserned it it gets sacraficed for the science.

I really love this host even if it is somewhat large.

[edit] Tested it. A real joy to see that amount of light! I guess it kind of “throws” ie. you can see far :slight_smile: but it lights up much larger area than any of my other lights. It seemed to start dimming some at about 30s or so at what point I ended the test. No need to destroy this fun toy. (It warms up pretty fast, not hot at that time though. I guess I should have leveled the pill before glueing on the led). I’ll be returning to 4A level I guess.

The Y3 is a great light thats for sure.
But I wonder if anyone tried to put this LD34 driver into this light, the stock driver has 22ish mm and that driver has 23,6 according to spec (haven’t seen an exact masurement). It has an on board switch that could fit. It has a voltage range up to 8,4V and uses constant current regulation. The UI is good imo(Convoy L4). You might even change the current with the Key-Set method that “Simon” posted somewhere (Has to be checked). I don’t know if it works with MT-G2 LEDs but CC would be a great benefit. Sould give you great efficency in lower modes.

edit: Whoops just noticed that the stock driver is a 23ish mm driver so that makes the task in hand a lot easier. Might be a perfekt fit, the little knob won’t fit anyways so you either have to drill a hole or just file it of.

Just an update on the modding progress on my two Y3’s…

Both are in 2-cell configuration. Both have the emitters on maxtoch mcpcb’s, shimmed up using flattened copper pipe that’s roughly the same thickness as the mcpcb, with the shims soldered to the bottom of the mcpcbs. One has a dedomed stock XM-L2 - resistor modded with an R100 added (total resistance 0.045), pulling roughly 5A measured at the LED using my DMM (after everything I learned in this thread, it’s now sporting bigger 14ga leads, soldered in place). The throw is pretty good, but I wouldn’t consider it mind-blowing. I haven’t really tested it anywhere I can reach out more than 400 yards (which it hits somewhat easily), though. It’s a rather useful beam pattern - plenty of spill, large-ish hotspot. Seems to be relatively focused (no donut on the wall past about 6 inches out). I do like it a lot more than other ‘throwers’ I’ve built (which is limited to basically a modded C8 with dedomed XP-G2 driven hard and focused well in a smooth reflector). Turns out I really don’t care much for pencil beams. So I like the beam on the Y3 with the dedomed XM-L2. Not crazy about the tint, so it may get swapped out at some point.

Main reason I’m posting is because of my other Y3… I reflowed a higher bin MT-G2 (Q0) where there was previously a dedomed (sliced + LED seal) P0 bin MT-G2. Driver is modded with the R150 removed, and two R100’s added for a total resistance of 0.03913. Measured around 6A on high at the emitter.

The results are… spectacular. This light is freaking awesome. Heat transfer seems to be pretty good, and now that it’s cold outside it’s not getting remotely near ‘too hot’ - Only getting mildly warm. With the other MT-G2 it would get sorta hot after a few minutes when the ambient temp was around 70F, but the head seems to shed heat rather well.

This has instantly become my favorite light. I’ll try to take some beamshots tonight to show y’all what I’m talking about. I’m new to taking beamshots… are there any standard-ish lights out there that would be helpful comparisons? Most all of my lights are modded in some way or another (some more extensively than others)… only lights I have that are currently unmodded are a Nitecore P12, and a mini Mag LED Pro+. Also have a Solarstorm SC02 that has only had a UCL added but is otherwise stock (for now). So if one of those would be helpful, please let me know. I do have two other working MT-G2 lights if that would help - a Convoy C8 with an MT-G2 P0 (brass pill, smooth reflector, AR lens) driven at around 4.5A and a SF L2M with the sliced P0 formerly in my Y3 driven at 3.04A (may be stacking more 7135’s on tonight, it’s feeling weak and needy at 3A). Also, what is more helpful, a longer shot before trees/objects (200 yards) or a shorter one (25 yards)?

Dang, g-man, these sound like awesome modded Y3's! Too bad you don't have a light meter to measure throw. I would think your de-domed XM-L2 should be doing over 200 kcd, maybe close to 250 kcd, in that range. Where did u get the Q0 bin MT-G2?

My vote for beamshots would be to do both distances Smile! I've been using UCLp's in the Y3.

Got the Q0 from intl-outdoor. I don’t think I’ve seen the Q0 bin anywhere else yet. I wanted both that and a 16mm noctigon for an MT-G2, so bought the Q0 already mounted from IO, then when it arrived, I pulled both the Q0 and dedomed P0 and reflowed the Q0 onto the maxtoch mcpcb and the P0 onto the 16mm noctigon. So now the dedomed P0 resides in a P60 dropin. The tint is rather warm for my taste with the dome sliced. I didn’t notice any substantial improvement in throw, but it could just be the tint messing with my eyes.

On a related side note, an L2M with the stock 18350/16340 to 18650 extension removed and a longer 18650 extension added it fits two 18500’s perfectly. So the size is pretty darn small (and awesome) for an MT-G2 light. Just not crazy about the tint and output quite yet. I think more power is the solution. Or that emitter may end up living in a mini Mag modded to fit a P60 pill and another MT-G2 altogether may end up in the L2M. Yes, I know I have a problem. Once you start down the modding path, you just can’t stop.

It’s fair to assume that the LD34 may be of higher quality than the stock driver, but the stock driver is a ‘CC’ buck driver. Tom E has seen inside an LD34, maybe he has pictures?

Sorry, checked my pics of the L4 and didn't have anything on the stock driver. I really don't care for the L4's UI - hate side switch's that can't turn the light ON and OFF, so I'd always want to replace it if I could.

Wasn't aware the LD34 is PWM-less - if so, pretty awesome, but again, lacking an ON/OFF ability is critical to me.

Well, i tried modding my Y3 the same way, but whatever i do i cant pass 3.5 amps with ld 1 driver, too many wires and crossings, and that driver is great! It shines in my c12, yet, Y3 is a way better thrower plus, has way better thermal management

P.S my Y3 default driver is a disaster, 2amp max on a fresh 18650 PF/b/26650 TF( same for all± 0.1 amp)…and my DMM is Benning…

We need details! Smile. 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 Frown. 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.

I think Small Sun ZY-T13 is the one you had in mind with 2 cell no details.

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.