Thorfire BL01 Bike Light Review

Thorfire BL01 Bike Light Review
(Sample provided by Banggood.com for Review)

Banggood graciously agreed to provide me this Thorfire BL01 Bike Light Taillight Combination in exchange for a review. Even though the light was provided free of charge my review will be unbiased.

Banggood sells the Thorfire BL01 Bike Light Taillight Combination here for $32.61 (as of date of this writing). Thorfire’s product page is here. Note the very reasonable lumen ratings from Thorfire. *NOTE: Banggood has pulled the product from the webpage at this time and should be returning it in the future. Until then, they have asked that I provide you the following link: http://bit.lc/4gA5 .

Shipment from Banggood took 18 days from date of placed order until the day I received it (this was standard China EMS shipping with tracking). Note that my shipping experiences have been very positive with Banggood. I placed an order 5 days prior to this Bike Light and even though that order was split into two shipments, both arrived 12 days later. The Thorfire light combo was well-packaged and came in a nice cardboard box:

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Inside the package were the lighthead, taillight, battery pack (arriving at a good storage voltage of 3.80v), battery pouch, two foreign wall outlet adapters, o-rings for lighthead mounting, mount for the taillight, battery charger, and two USB –> DC adapter cables (USB to male DC and USB to female DC). One of the USB adapters is used to charge the battery pack. The battery charger wall wart has USB output for the cable connection. The other USB cable has the female DC end on it, so I can only surmise that it would be to power the light from a USB Power Bank, though you’d need a power bank that can supply enough current with tripping protection. (I tried with my ENB 3x18650 power bnk rated 1A output and it kept tripping it’s protection.) Also in the box were a card asking if I was happy (providing details on how to post a review on Amazon) and a nicely written English user manual containing operating instructions and specs. (Interestingly enough listing modes as “800 lumens, 450 lumens, and 100 lumens” while their website claims “674, 240, and 85”.)

The light includes a warranty from Thorfire guaranteeing repair for manufacturer defects within 20 days, repair of a light free of charge within 24 months, and charging only for parts beyond 24 months.

Thorfire has built a good reputation in the budget flashlight world and so I was curious to check out one of their bike light offerings. The light itself is of very nice quality. It’s a definite step above the cheap no-name junk out there. The light body is aluminum, the lens is glass, the bezel appears to actually be stainless steel and not just polished aluminum, and the handlebar mount is even aluminum. The red metal switch button has a nice solid feel to it and functions flawlessly for changing modes. The button is large enough and protrudes enough that operating it with gloves on should not be a problem. The clear ring around the button displays the battery level status changing from blue to yellow and then to red. I found this battery indicator light to be too bright and not very helpful changing to yellow after only the first few minutes (3.68v after 8 minutes on high) and not changing to red until the battery was fully depleted (3.08v during my runtime test).

The modes of the headlight are High~~Medium~~>Low then back to High to repeat the cycle. To turn the light off you press and hold the button. To access the hidden strobe you give the button a quick double-click. The driver’s output is not regulated so therefore output declines slowly over time (note: see driver section below for more on this). One nice feature is that when the battery pack is depleted, instead of the light going off it drops to a very low output level and blinks about every 3 seconds. Tint is a very crisp cool white without any hints of blue, green, or yellow – my guess would be a “1A”. Thofire claims the LED bin to be a U2 which is believable. The light uses an orange peel textured reflector which results in a nice throwing beam with a smooth transition to bright spill. I would say it will easily light up objects out to 250 feet.

This light is a 4.2v light as opposed to the majority of lights which are 8.4v. DO NOT connect this light to an 8.4v 2S2P battery pack! Current draw on the stock battery is 2.68A on high, 1.34A on medium, and 0.26A on low which yields mode spacings of 100, 50 and 10. PWM shows up in my camera on medium and low but I cannot detect it with my eyes. Low being 10 is a bit lower than I would prefer, but some may find it acceptable.

I also tested light output in my new D.I.Y. 12 inch round polystyrene integrating sphere and measured the following:

Mode At Start At 30seconds
High 800gbl 790gbl
Med 400gbl 400gbl
Low 80gbl 80gbl

(*gbl=”garrybunk-lumens” which should relate closely to “true” lumens, however due to my lack of calibration lights I cannot provide any guarantees.)

Beamshots:
Note: On the evening I planned to take beamshots there were snow flurries so my “across the backyard” photos did not turn out well. I then retook beamshots on another day, however in my rush to get the shots didn’t notice that my manual camera settings were set wrong and so those shots are overexposed making the light look brighter than it really is (I shot at a shutter speed of 1.6sec instead of 1/1.6sec). Here are the shots taken during snow flurries:
Backyard, +/- 185 feet to the trees. High, Medium, then low:

High:

Med:

Low:

My “Simulated Wooded Trail” Setting, High, Med, then Low:

High:

Med:

Low:

Disassembly of the light is accomplished by unscrewing the bezel at the front and the clear ring around the button at the rear. Removing the bezel and glass lens reveals a fairly thick o-ring in use to keep the light waterproof (yet untested). An LED centering ring (“butterfly” type) is used to keep the reflector perfectly centered. The LED emitter is mounted on a standard 20mm aluminum pcb and ample thermal compound was used in mating it to the solid wall of aluminum behind it resulting in a direct thermal path to the outside airflow for very good heat dissipation. The wiring from the driver to the emitter pcb looks to be of sufficient gauge and not too thin.

Disassembly of the rear of the light shows the clear piece to have another fairly thick o-ring and driver to be glued in place along with the cabling at the entrance hole (which should provide ample waterproofing (yet untested). I tried to remove the driver, but was unable to without fear of destroying it so I left it alone. (I may try again after you read what happened to my driver further below.)

The battery pack arrived looking like your typical blue shrink-wrapped 4 cell pack and came at a good storage level of 3.80v. The pack comes with the generally preferred MagicShine style plug and the usually cheap pouch. Upon opening the shrink wrap I found unmarked white cells with very good weld joints to the connection strips. The protection circuit was wrapped well in kapton tape with more kapton tape used as protection on the cells the circuit rests against. The protection circuit utilizes two 8205A MOSFETs. I did not test over-discharge protection, but I believe I saw over-charge protection kick in at 4.19v as the battery charger seemed to depend on the battery pack’s protection circuit to end the charge process.

I had my doubts as to the quality of the battery pack. I discharged tested the pack on my hobby charger at 2.0A and saw a surprising 8,937mAh capacity! This was also only the first full cycle of the pack! I was quite impressed!

Being a 4.2v pack you could easily make a homemade adapter to charge it in a quality lithium ion charger like so (just the wood dowel end):

The charger is a big disappointment and is not really a charger at all. From what I can tell it’s simply a 5v USB wall adapter. It did not appear to follow the proper CC/CV charging algorithm at all. Unloaded it puts out 4.98v. When charging the battery pack the charge current ranges from 2.06A to about 1.32A decreasing as the pack’s voltage rises. As stated above, it appears to rely on the battery pack’s protection circuit to cutoff the charging process. The “charger” is rated for worldwide voltage (100v to 240v) and includes various outlet adapters, though US use does not require any of the adapters. The wall adapter was getting very hot while charging the pack.

I did a runtime test with the light on high mode and a small fan blowing across it. I monitored the voltage and current on the battery pack during the test as well. The light ran for a total of 5hrs 18 mins where it then dropped to a very low output level (0.05A) and flashed every 3 seconds. Output slowly declined during the entire duration of the test and just before it ended was only pulling 0.76A and measuring +/-275gbl’s. See the following time lapse video for the runtime test:

https://www.youtube.com/watch?v=NM15KDNq904

I also performed a thermal test to see if/how the light managed heat. The answer is simple – it doesn’t! There is no thermal protection whatsoever. During the course of my test the lighthead body took awhile to heat up, but when it did it kept rising until it reached a temperature of 155° F at the 20 minute mark (end of my test) and showed no signs of stepping down power output. The lighthead felt scorching hot to the touch! I recorded a time lapse video of this test in which you will see a timer set for 15 minutes and then reset for another 5 minutes. Here is that video:

https://www.youtube.com/watch?v=4orjoyDrzqw

Lastly I attempted to power the light from a DC power supply in order to do some further testing but mistakenly set the power supply to 8.4v. (I was in a hurry and forgot this was a 4.2v light.) The light worked for a short time and then something in the circuitry must have burned up as now it comes on immediately dimly lit and does not change modes nor turn off. Being a 4.2v light though there would be numerous options for flashlight drivers loaded with custom firmware to replace it with.

Since the driver is now blown I have gone ahead and forced it out in order to see the other side of it. If I can’t get help repairing it I may eventually replace it with a customized driver also swapping the emitter to neutral white of course. (This would not be high on my todo list though.) The driver was not that hard to remove with force. I scraped away as much glue as I could, unsoldered the emitter leads, and pushed through the emitter wire holes on the front side forcing the driver to pop loose. On the backside of the driver I found (7) 7135 current regulator chips of the 380mA variety! 7 x 380mA = 2,660mA or 2.66A, corresponding well to my current measurement of 2.68A. So this driver does regulate output current, however I suspect that operating at only 4.2v voltage sagging due to losses in the cables is causing the output to drop out of regulation rather quickly. In my previous testing of a 4.2v light I found that I had to increase my power cables to 18ga in order to overcome the losses. That would be my recommendation here – replace the cabling with short 18ga leads which could work well for a helmet mount with battery pack on the rear of the helmet. Another thing about the driver, I wouldn’t be surprised at all if the microcontroller used is actually an Atmel ATtiny 13A. It looks like one though the chip markings are rubbed off. This would open up the possibility of flashing custom firmware same as being done on flashlight drivers! You could also stack current regulators to increase output, assuming the cabling could hold up to the increased demand.

Some specs:
Light body diameter – 32.5mm
Length – 59.9mm
Reflector – 26.4mm wide by 18.6mm deep\
Fins – 3.9mm deep
Button – 14.9mm diameter
Glass Lens – 29.7mm (No AR Coating)
Emitter PCB – Standard 20mm

Conclusion: This is a very nice well constructed light with a beam pattern that has a good mix of throw and spill. The attention to details such as the sizeable o-rings, glue sealing the power cabling entrance, use of kapton tape protection in the battery pack, and aluminum mount are appreciated and show that Thorfire was concerned about making a quality product. Where Thorfire fell short is in the battery charger. I would highly recommending not using the included charger and getting an appropriate one. Some other missing features are the driver not having thermal protection (i.e. stepdown) and the battery indicator lights not giving a good indicator of battery life. However, for the price of $32.61 it’s not a bad deal at all!

I thank Banggood for supplying this light for review. I have encouraged them to try to stock more light options. Hopefully they will listen.

I leave you with more photos. Here is a link to my full gallery. I have purposely left out the tail light since the headlight was the main object of review. The tail light is “typical” and just simply a nice thrown in “extra”. Perhaps in the near future I will add some details on it as well.

Note: Review also posted at MTBR’s Lights & Night Riding Forum.

Thank you,
-Garry

Reserved for Tail light.

-Garry

I have some questions about the battery that some here might be able to answer. It looks as if the batteries are in parallel and are not individually protected. In other words, the protection circuit is applied to all four cells at once.

What would happen were they to become unbalanced? Would it be possible for one cell to discharge to a dangerously low voltage? Would it be possible to overcharge one cell, or is the voltage seen by the circuit the maxium voltage of all four cells?

What would happen if the battery pack was placed in water? Would they short out and hence vent?

There is no mechanism to restrain the wire, hence it is possible to pull the wire away. Is this a safety issue?

Regarding the driver, the MCU would not be Attiny13A because the Batt+ is connected to the pin 4 which should be the ground (Batt-).

Nice review gb. Thanks.

Ah, gotcha. I never looked that close to compare.

-Garry

First of all the cells are all welded in parallel so they will always discharge & charge evenly. There will be no “going out of balance” like you get with the typical 2S2P packs. This assumes starting with matched cells; not sure how they’d behave mismatched though I still doubt it would be a danger. Secondly, protection on the pack as a whole is pretty normal. I think it’s actually more problematic having each cell individually protected.

I do wonder about the water issue. My suspicion is that with good cells you’d get nothing more than corrosion / dead components on the PCM (ever taken apart a li-ion power tool battery that got water in it?). We already know that the notion that the DC power plugs need to make a waterproof connection is false. If that were true every outdoor electrical connection would need to be waterproof (i.e. every connection on the outside of your automobile). I’d be tempted to throw a cheap Chinese pack in a bucket of water just to test this,

Yes, the wiring not being secured could be an issue if the cable got snagged. I don’t think it’s a huge issue, but that depends on how prone you are to it snagging.

-Garry

Hello Garry. Thank you, very informative.

Nice review Gary. I’m glad to see you are still involved in the cycling culture.

Thanks for the thorough review, including a full breakdown, nice!
I feel sorry that the driver broke because the light could have been useful after review.

Mismatched in sence if they would accidentally put 3 pcs with 2200mAh and one with let’s say 2600mAh?
Because they are all in parallel, cells with lower capacity would slightly overcharge and cell with higher capacity would be slightly undercharged, as if they are all 2300mAh.
A least theoretically :slight_smile:

I realized I missed adding the driver diameter to the review. From memory I’m pretty sure it’s 23.6mm.

I also forgot to add the battery pack discharge test graph. Here it is:

-Garry