Review : Utorch UT02 Flashlight (XHP35 / 26650 / usb rechargeable)(in progress)

Mitko, can you tell us where the driver is likely to fail? Thanks for any help here

Most likely the power elements: the coil and mosfets: i`ve examined only 1 of those failed drivers actualy cause its hella time consuming and those elements were fried, prolly due to the heat caused
cooling this driver is a must btw, it heats alot, those lovely sillicone cubes will help

Also using a 1206 as a mod R would be good too, the resistor also generates lotsa heat so a bigger one is actualy a good idea

Hi, which batteries does mitko use? I measured different distances, with liitokalas and does not exceed 119000 cd in 7 meters, greetings !!

Efest Purple 4200 with a bypassed front spring ofc, on some of those torches the centering ring needs to be tuned too( usualy sanded a bit, but only an idea)

I dont have a reliable Liitokala source anymore….EU regulations… i have a feeling they will ban flashlights sooner or later

Thanks for your prompt reply, regards!

So it’s safe to mod with a 100R resistor?
Is wiser to use some silicone heat transfer cubes with just the 100R only mod?

I was about to buy it because of the 33 USD deal, but then I read a few reviews and I really don’t like the fact the the led is underdriven. Actually I was looking for thrower bigger than my C8 (not huge like the convoy L6, still easy to carry), without spending too much, but I don’t think this UT02 will significally outperform my C8 with XP-L HI and FET+7135 driver… so what’s the point in carrying a bulkier flashlight?

I mean, the host looks awesome, but considering the 12V Led and the electronic switch, I don’t think it’s easy to swap just the driver (I wouldn’t care losing the charging if the led is driver at its full potential). The people who had the failed driver, what have you used to replace it?

Of course modding the original driver is always an option, but this particular light seems to have an easy failing driver even in stock, like stated in the posts above…

I a bit confused :s what would you suggest? Also the deal is ending very soon…

I am trying to remove the head from the battery tube but it seems to be stuck. Is it glued on?

I have the same question.

Lj , is your led centering ring black too ?

If yes , they are probably glueing them in the last batch

Yes, the centering ring is black.
Any recommendations on breaking the glue?

Heat and strap wrenches, for heat you can put it in boiling water, inside of a waterproof bag, the temp will never rise above 100°C, use gloves.

That is how I managed to open my TN-31

Thanks Alex, I’ll give that a try. I assume wrapping the torch with a piece of thin rubber and using a nylon strap wrench would be best.

Ok, so I don’t have any strap wrenches, so I improvised….!


I tied some pieces of paracord to two screw drivers and wrapped two pieces of thin rubber around the body and head of the light. Then I wrapped the paracord in opposite directions several times until tight and used the screwdrivers as leverage. Same principle as using strap wrenches.
No heat required, just brute force :sunglasses:

Great work! :+1: Tomorrow I will do mine! And add some resistor to bump up the current to a bigger but safe level.

Thanks.
What resistor value are you going for? I’ve got some 100 Ohm resistor’s that I’m going to try.

Do you mean R100 labeled resistor? That is 0,1 Ohm. I have a lot R100 so I try it with that.

Yeah I meant R100 not 100 Ohms :person_facepalming:

In case anyone is curious, this light will work with a 3xAAA battery adapter as a power source. Out of curiosity, I tried it with some fresh AAA Eneloops. Turbo mode didn’t work but on High it was getting in the range of 400-500 lumens. The battery indicator was red in this mode due to the voltage. Not too shabby although I’m sure the runtime would not be good on High. I was considering gifting one with a NiMH option to someone who didn’t own lithium batteries.

I’ve had UT02 before and lost it.
Today I received a new one and noticed a big drop in quality:

  • the USB port cover is very flimsy
  • I got a nearly 2 mm dust particle inside reflector as well as small amount of fine dust
  • There’s ~1 mm gap between the head and the battery tube. I see grease shining in it.