Review of the MagicShine MJ-808

[oh_blinding_light]

Time for another mind numbing technical article from OBL!

Some of you saw the incredibly cheap Chinese made 10 watt LED headlight I brought as a spare to this years Santa-Fada /Christmas ride. They sell for between $80 and $90, there are 2 distributors that I know of in the US, at least 2 in China, and a few folks selling them on ebay. If you google for magicshine you'll find the two us distributors on the first couple pages of results. One has a URL that begins with geo, the other has singletrack in it's name. PM me if you want the URLs after reading my review, and can't find them.

The light looks like this:



It's becoming clear to me from reading various online forums over the last couple of weeks that this thing is spreading like a virus, lots of folks are buying them. I could recuse myself because I am a potential competitor to this light (some of you have seen my BFL-1000 lights and a few of you own them), but I won't. Since I am a potential competitor, you are welcome to assume that I am biased and take my review with a grain or 3 of salt. I'll talk about why I may not be as biased anymore after the review.

OK on to the analysis.

Light name: MagicShine MJ-808

Manufacturer: Minjun Electronic http://www.headlamp.cn

Power supply: Lithium Ion battery (four 18650 cells), configured as 7.4 volt 4400 mAh (about 32 watts).

Output: 900 lumens claimed, probably a little less than 700 lumens actual. Still pretty bright for the price.

Modes: 3 or 5, depends on which version you buy.

Runtime: 3+ hours on high.

Quick synopsis:

Pros: cheap, looks nice, bright, did I mention cheap.

Cons: poor quality and reliability issues.

The long tedious version of the review

The light's case looks fabulous. It's made of aluminum that has been well machined and anodized. It looks very much like the Lupine Tesla bike light. A lot of ideas were copied from the Tesla, the O-ring mounting system being the most obvious.

The beam pattern is pretty decent, in some respects I like it better than the beam on my own BFL-1000. It has a wider hot spot and not quite as much spill, but the spill is brighter. I'll try to post some beam shots that compare it to my BFL-1000 later.

The light came out late last spring, so I ordered one from the DX China site, and it showed up in early June: Once I started playing around with it my first thought was: "Oh, pooh (well another word actually but this is a PG rated forum), I guess I'm gonna stop making bike lights."

About the same time I got mine, I started reading in one forum how bad the build quality was, so I opened mine up. It had metal shavings in the compartment that held the electronics. There was nothing to prevent one of these shavings from falling across some high current electronic part, shorting it out, and making the light die, most likely without any warning. One of the US distributors claims that this problem has been fixed. And recent posts from folks who have dissected their lights indicate this seems to be true.

I also noticed a few design problems:

One problem was there wasn't very good heatsinking in the light-head, actually in my light there was none. LED lights are around 3 to 4 times as efficient at turning electricity into visible light as an incandescent light, but they still produce a lot of heat. An incandescent will produce a good chunk of that heat as IR (infrared radiation) and will radiate it away from the bulb. That's why you can feel heat when you hold your hand in front of a halogen light. Hold you hand in front of an LED and you'll feel nothing. But that excess heat still must be taken away or the LED will overheat and stop working (or at the very least have it's lifetime shortened). The manufacturer has supposedly improved heat-sinking to fix this problem, but I have some ideas on how to fix this that may be better (more on this later).

The second problem is some of the components are not designed to handle the current run thru them. As one example, there are 2 resistors on the main driver board that are designed to dissipate 1/8th of a watt. One has enuff current running thru it that it needs to dissipate almost 1/2 a watt. In tests I and other members of one of my favorite DIY bike forum showed that a lot of the components on the driver board were running very hot (like near the boiling point of water). Parts running this hot usually have a greatly shortened lifetime.

Another issue, is the light appears to have no way to lower the LED output if the electronics get too hot. Most US manufacturers use some kind of temperature feedback loop to dim the light when it starts to get too hot. If you are riding at even a slow pace, say 4 or 5 mph, there will be enuff airflow over the light to keep it pretty cool. If you stop for more than 5 minutes, you should switch the light to low (or maybe medium if you have one of the 5 mode lights). When the light gets hot enough that it's painful to hold in your bare hand it has reached a temperature around 50 degrees C. That's a good time to turn it down.

The cable running from the light to the battery pack uses pretty thin 20 gauge wire. This is a bit thin for the current it needs to carry, and is pretty easy to break, either by catching it on some obstacle or by repeatedly flexing it. The wire uses PVC insulation, which is rated for 80 degrees C (80 C from now on). Since some folks have measured the light housing as getting up to 90 C in still air, I'm a bit worried about how well the cable will hold up.

The screw that holds the mounting bracket to the case is only hanging onto the case by 3 or 4 threads. You can replace the screw with a slightly longer one if you have a good source of metric screws. There have been a few reports of the mounting bracket breaking.

The battery pack is made up of generic Lithium Ion (Li-Ion) 18650 cells. There is a protection board to help keep the battery from being overvoltaged (makes 'em go boom during charging) or drained too low (sometimes makes them go boom during charging). It does not appear to me that there is an actual fuse on the protection board, which most reputable battery companies put on a Li-Ion battery pack. The battery pack is probably made up of pretty inexpensive 18650 cells made in China. My experience with inexpensive 18650 Lithium Ion cells has been mixed. These batteries can explode into flames if abused, treat them with respect. Never charge a cold Li-Ion pack, let it come up to room temperature first. Never charge a Li-Ion pack unattended (I charge mine outside on my driveway in a metal bucket if I won't be around to keep an eye on them). Don't leave a Li-Ion pack plugged into it's charger once the charger indicates that it's done.

The user interface is kind of bogus. In the 3 mode version when you push the button on the back of the light you cycle thru: Hi, low, flash, off then back to hi. I find it kind of annoying you have to turn the light off to get from low back to hi. The 5 mode version has a mid brightness level and 2 blinking modes you have to cycle thru to get back to high. The couple of test rides I've done with the light I've just kept it on high. I have the 3 mode version.

The manufacturer claims the housing is waterproof. When I took mine apart I noticed there was no seal where the power cable went into the housing, and nothing sealing the screw that holds the mounting bracket on. The light is probably not going to have any problems in rain, since the unsealed parts are on the bottom of the light. There's a youtube video out there showing someone plunging their MagicShine light into a swimming pool. Kids, don't try this at home , it will work for a while but will eventually fill up with water.

And finally, there wasn't a user manual with my light. That seems odd given that you need to be careful charging Li-Ion batteries, and you'd think they would at least mention to turn the light down to low when stopped to prevent overheating. At least one of the US distributors is including an instruction sheet with the light (in English even).

There were a raft of problems reported by early users. There is an online poll that indicates about 8% of all customers have had at least one significant problem with their light: http://forums.mtbr.com/poll.php?do=showresults&pollid=2407

The poll may not be accurate because there have been a lot of arguments between folks who love the light and folks who don't.

Here are a few suggestions for fixing the light that were posted on: http://forums.mtbr.com/forumdisplay.php?f=124, a forum for folks who light to build their own bike lights.

Never plug the light into a battery with a different polarity (ie: the positive and negative wires are swapped). At least one user did this and blew out the light.

The battery pack is not waterproof. If riding in rain, be sure to put the battery in a plastic bag. The protection board in the battery pack is very moisture sensitive.

The charger has caught on fire on at least one occasion that I am aware of. The charger probably has a bogus CE (sort of a European version of UL) mark on it. I have heard that newer versions of the charger may have a bogus UL mark on them. If this is true, then I am a bit upset with the manufacturer. It's one thing to make and sell a cheaper product while playing by the rules. It's pretty dishonest to sell something cheaper with markings that make consumers think they are buying something that has been well tested.

But enuff about the light, let's talk about me

For those who haven't met me or ridden with me at night, I make LED bike lights, as a hobby, with an eye to someday, maybe, turning pro. LED technology is evolving pretty rapidly, and for the last few years a small group of a couple of hundred DIY (do it yourself) bike light builders have pretty consistently stayed ahead of the large lighting manufacturers in producing some amazing lights. There have been a few pretty active online forums discussing how to build your own LED lights. I've been active in these forums, sharing ideas with other builders and building a number of lights. I have a background in electrical engineering, know how to design circuits, lay out printed circuit boards, solder, all that stuff. And working on these lights has been a fun break from the dreary software consulting I do to support myself. I mention all this to let those who don't know me get a sense of my background.

When the MJ-808 came out last spring, many on the DIY forums announced it was the death of the DIY bikelight movement. As folks dissected lights, and saw how shoddy they were, quite a few of us decided that this light probably wouldn't last on the market for very long. Most of us went back to building and designing our own lights

But once Daylight Savings Time want away, interest in the MagicShine really took off. I cant' blame people for being interested. It's a very bright light for the price, and from the outside the build quality looks pretty good. The postings I've seen online remind me that it's not always wise to drink the KoolAid. Is the light bright ... yes. Is it as bright as lights costing 3 to 4 times as much .. yes. Is it as reliable as lights costing more ... in my opinion no (but, hey I'm biased, maybe).

I have pretty much decided to drop the idea of selling the BFL-1000 bike light because I can't compete at an $85 price (those of you who bought one from me, I have enuff spares to cover your warranty). Is my light better? Yes, I think mine will last longer (maybe 10s of thousands of hours vs. several hundred hours for the MJ-808). I think my user interface is better. I like the idea of letting the user choose what battery they want to use. I'm planning on only selling NiMh batteries. I think selling Li-Ion would be a legal liability issue I wouldn't want to tackle, but I'll be happy to show folks where to get Li-Ion batteries and how to wire them up. I know my light is lighter and more reliable. But with no advertising budget it's pretty hard to compete with the buzz generated by all the people who seem to love this light (mostly because it's so inexpensive).

So I've decided to focus on my BFL-2001 light design. I figure twice the light for a bit less than twice the money of a MJ-808 might be a winner. Any comments or suggestions would be welcome.

Some things to consider if you get a MagicShine for Xmas:

Electronics exhibit a behavior called "infant mortality" in the trade. Basically if you can run some electronic device for several hours before shipping it to a customer, and it still works when shipped, there's less of a chance you'll get it back. If you ship it after you just soldered it together, you'll get more returns. I suspect Minjun Electronics is counting on customers finding defects for them. Since the light has a 90 day warranty, I'd suggest you use it a lot during that time. Return it if you experience problems. Returning stuff to one of the Chinese distributors is usually a long and frustrating experience.

If you can't go riding, set the light up someplace where you can run a fan over the light-head (airflow prevents it from overheating). If the light-head gets too hot to pick up, crank up the fan, or turn the light off and let it cool for a while. Never run the light on high with no air flowing over it. It will burn up and die, or at least get pretty dim and never be bright and shiny again.

Never run the battery all the way down (some users report the light blinks when you let the battery get too low). I'd suggest just running it till the switch turns red, indicating the battery is starting to get low.

Run the light and battery thru a bunch of charge discharge cycles. If your charger, gets hot, or the battery fails to charge properly, return them to the distributor you got it from.

Unplug the battery when not using the light for more than a couple of hours. The green glow the switch gives off will drain your battery in a few days.

Always unplug the battery when putting the light in a pack. I've heard of too many people who had the light turn on and burn itself out.

When riding with this light, always, always bring a backup light.

If after reading my review, you still want one:

The US distributors will sell just the light-head without the battery as an option. If you are intrigued by the light and have a decent 7.4 volt Li-Ion battery (or 7.2 volt NiMh battery) to run the light-head with. I'll also try to post a few batteries and chargers from allbattery.com and batteryspace.com that should work.

I modified my light-head to run at higher voltages than 7.4 (don't try this with a stock unit, it might work for a few minutes but will probably die after an hour or more). While I was at it I added a beefier cable (14 gauge) and coated the electronics in heat conducting epoxy. I also epoxied the LED in place with this stuff and glued all the metal pieces that connect to the outer case together. I'll never get my light apart again, but it warms up much faster now. I'd like to post instructions on how to do what I did, but neglected to take pictures while I was gluing the light together.

If you get a MJ-808 for Xmas and want to have it modded like mine, I'll be happy, at no charge, to modify the light to have better heat sinking, and a higher voltage range, for free to the first 3 folks who take me up on the offer. After I do one or two I'll post step by step instructions for anybody else who wants to do it. For folks who don't know how to solder, I may offer to do mods for some nominal fee (probably $10 to $20, heat conductive epoxy is expensive and I didn't record how much I used).

Wow it sucks to live in a country that has product liability laws and compete with a country that has none!

Have a nice holidays!

OBL

PS: Chinese Distributors are dealextreme.com and kaidomain.com.

PPS: Why don't I mention the US distributors? I got into an argument with one online and don't care to send business his way. Let's just say if I buy another MJ-808 light-head it will be from the place that has singletrack in it's name.

PPPS: This time of year it will be faster to buy a light-head from one of the US distributors. If you order from China, be sure to get your order in well before the Chinese New Year. The whole country pretty much shuts down for 2 weeks.
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Nimium est melior!

[slave2bacon]

My opinion, buy local. 'Nuff said.

[Riceball]

My opinion, buy local. 'Nuff said


I'm with bacon guy...

Well said OBL...

Support local innovation and product development.
Stop shipping production overseas.
Jobs follow!
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Grumpy is my happy place.

[oh_blinding_light]

Found a guy in Australia who is a distributor for these lights and has a free manual on his web site. The light as sold from the Chinese distributors doesn't come with a manual, in my opinion another indication of the care that went into building this product

Anyway you can find the manual here: http://www.magiclight.co.za/userguide

If you bought one of these the key sections in the manual are charging and keeping airflow over the light when running it on high.

And I'd add, don't ever leave the battery charging unattended. I charge my inexpensive Chinese LiIon batteries in a metal bucket out on the driveway in the summer, or in an old military surplus ammo box next to my desk in the winter (and keep my fingers crossed).

I must have scared everybody off with my review, 'cause nobody has contacted me about improving their MagicShine.

OBL
_________________
Nimium est melior!