Your welcome and thank you for reporting back!
I am a little disappointed that the bigger wire did not make much of a difference… I was really hoping it bumped up the amps, knowing this I will probably not replace the wires just yet.
Yeah, the original SRK does seem more blueish even being that it is a U2 bin. As for brightness indoors, the Kung did have a noticeable difference however it did not show as much on the picture. The flashlights were about 5ft away from my sand colored wall.
Well the Kung is 6500 “Chinese lumens” 
You definitely must have a different version of SRK or Kung (or both). I know my SRK is pretty good due to comparing it to the J18’s output, but I really expected the Kung to overpower it visually, but tint makes it hard to judge (J18 being much brighter is because J18 is 8000 Chinese lumens too ). The Kung does seem like its a “thrown together” light though too: driver was loose when I got it, tailcap also loose, and switch sometimes takes a second or so to actually turn on the light…could I have a switch issue guys? It does heat up pretty fast (5mins uncomfortably hot, 13min ungrippable really).
I’ve seen a review of the exact SRK I ordered. I feel safe saying mine is doing around 2200 lumens. My Kung does overpower the King. I hate to make this comment… Could you have gotten a bad one? I went over my light pretty thoroughly. The switch rattles a bit but other than that no real issues. I think many of the light issues stem from this… The China based company’s play it like this… They put out light after light…Not many, but enough to see which will garner interest. When a light ‘hits’ & many people start buying them. The Chinese manufacturers start slapping them together just as fast as they can.From a profit view that’s awesome. But from a quality view it sucks. This is why many of the ‘first run’ lights tend to be superior to later batches. JMHO
P.S. Have you seen the way these things are selling in Ebay? It’s crazy… I imagine the company’s over there are pulling double duty trying to keep up with demand.
Yeah thats what I’m thinking, that maybe my Kung is bad foo. Does yours get really hot fast? I used to think SRK heat was bad but Kung heat is much worse, without producing much more light. I think there has got to be some issue here if other’s Kungs dont heat up very fast…but I use good protected batteries and protection doesnt trip, runtime seems adequate. The only hints I have are fast heating and sometimes when I press the switch it may take a second to actually turn on.
Got a U2 version in today… some performance measurements here: SkyRay Kung M4 U2 performance measurements
I saw, is that the Gray one? Not sure I’m going to order the U2… Been seeing some poor stats on em.
Yes, but I think mine’s grey.
+1
Did some testing on the driver to see what could be done with it, and to try to figure it out.
Tested it with external power and leads soldered on and fixed load, wanted to see if it could supply 8 to 10 amps, wellll first the good news…. it can deliver 8 amps… now the bad news the MOSFETS at that current were blisteringly hot, had to quickly stop the test before they clapped. This driver IMO is fit for the round filing cabinet on the floor or at least my one is.
Will see if the controller can slave 7135s and also get away from paralleled LEDs, just have to wait on the 30 from FF.
On the standard set up got an extra 10% output by changing the wire to IO silicone and braiding/joining everything that did not move fast enough at the spring cap. I replicated the original wiring layout but will change that to individual wires to each emitter next and larger size. Also added heatsinks to the upper surface of the M’FETs to see if that has any effect (not sure they will) if the next wiring changes get the amps near the 8A mark.
Seems of good quality. Ordered from Rabitword88 on ebay with a winning bid of $43.
Machining is good, threads are greased and smooth, double GITD o-rings for the body. Anodizing is equal to that of most budget chinese lights.
Driver appears the same as Dales photo, credit for whoever pulled it out.
The crenelated bezel could be cleaner, but ill live with it.
Appears visibly brighter than my authentic NW King from CNQG, and of course puts out a dollop of light.
I took some cellphone whitewall beamshots but they were pretty poor so ill just wait to get the real camera out.
But for now the crappy cell glamour shots
Could you take a look if theres also “U2” on the stars?
Toppel
Received mine today. Ordered the black one from Rabbit. Got the grey one. Looks good. Switch isn’t loose like I’ve read above. Driver was very hard to get out. Thought I was going to break it. It did make some bad complaining sounds a couple times, but it still works. The driver is different from above. It is the same driver (don’t know about the resister values) as a SRK I got from BrotherH on Ebay a long time ago. Back then, that driver gave 4+ amps at the tail before changing emitter wires. Changing wires to 3 sets of 18 gauge on that light pushed current at the tail over 7amps with laptop pull batteries.
The emitters bases are white and only say “Cree” and “XML”.
Using one cold NCR18650A loosely held by hand while trying to hold leads and push switch button gave me 3.8 and 1.3 amps at the tail on high and low, respectively. Current would probably be higher with 4 cells and a more steady setup.
Here is a picture of the top of the driver. Sorry for not thinking of washing off all the flux on it:
+1
It’s dark so I put the light back together, no changes made to it. The beam pattern on this light is great. Smoother, bigger, brighter. Just knocked my SRK to a glove box light.
Interesting, a different driver, looks like a boost driver. Would be interested in knowing the tailcap current on four cells. Driver looks a little weak for four XM-Ls.
I might be able to get a reading in a couple nights. I don’t have enough charged cells as lights don’t see a lot of action this time of year. I expect the readings will be the same as I reported above on my SRK. The driver looks identical. Even has the same model number.
My numbers where sanded off my FET’s. I held them up to the light at just the right angle with a magnifying glass and I could make out the numbers. Pretty sure it reads D50NH 02L. The bottom line I think says 30V41U.
That appears to be the same driver in mine (same part number and holes). I have not taken my driver out.
Mine behaves like a direct drive driver. Tailcap current increases with voltage. If it was a buck driver, tail current would decrease as the voltage increased. If it was a boost driver it should have much better low voltage performance.
Pyro, that is curious. You’re right, a boost or buck driver would not behave as you describe.
I wonder what the coil is for then? :~