If this is the light you have http://www.dealextreme.com/details.dx/sku.13060 check out the post at the bottom called 'Low Current'

Thanks for the fast response guys. I have the light that Ziemas linked. The "low current" post didn't really make sense to me...does it mean he ordered a part for it and that fixed the problem?

Both of my lights use the 18650, and I think I've ruled out the battery as the problem, since the same battery will drive the 801 just fine but when I move it to the P7 I get blah.

I'll check the runtime probably tonight. I might be able to scratch up a multimeter from my garage, but it's been 20 years since I saw it...

According to the post I linked to the problem seem to be that the light isn't pulling enough juice from the battery to run the LED on full power, meaning that it isn't as bright as it could be.

What's the runtime of the light on high?

I'm regularly getting over 1 hour of runtime on high with protected Trustfire batteries.
As for brightness, this thing is easily brighter than my Trailtech 13W HID lamp. If the HID is 450 lumens, the P7 is 600 at least. The P7 is also several times brighter than my Fenix L2D.
With both the P7 and the HID on the other night, lots of cars were flashing their brights at me. That was pretty much overkill on most well lit streets.

Exactly which light do you have?

This one:
https://www.dealextreme.com/details.dx/sku.12623
Just two modes. Low is pretty darn low.
I wish the beam were less floody. Could use more throw.

There seems to be a lot a variation in these lights, even between ones of the same model. It makes me think that the specs are useless and the factories are just throwing the lights together willy-nilly with the parts on hand.

I ordered this one http://www.dealextreme.com/details.dx/sku.16500 and it's clearly not regulated as the specs say.

Yeah I agree. I did get the regulated batteries though.
QC is shoddy for these lights.

The batteries aren't regulated, they are protected. Regulated means that the light output is more or less constant throughout the charge of a battery. Protected means that the battery itself shuts down if it's over charged or under discharged.

Does any company out there sell a high-quality-controlled P7 flashlight? I'd love to give it a try, but I would prefer to deal with a company with high QC even if it costs double the amount for the light.

OK, I got some information...

I tested the runtime of my P7 tonight, and sometime between an hour and about an hour and 20 minutes the light became noticably dimmer on high, which seems to be about what most people are getting. I started the test inside, but the light was getting very hot--uncomfortably hot in my hand, so I moved the test outdoors.

I also took some pictures of the lights against my shed. Here's a link to the shots. Be sure to click "Detail" to see the descriptions.

I guess based on the pictures that I was just expecting too much from this light.

Remember, a light with 2x as many lumens as another light will not appear 2x as bright as another light; to perceive 2x the intensity, you need 4x the lumen output.

This is part of why I haven't bought a second P7; I know the two wouldn't appear twice as bright as a single light. Another reason is because I don't really feel I need a second; yet another reason is because I'm waiting for one light that would be bright enough to sit on the handlebar and relegate the P7 to being a backup light stored in my backpack.

By the way, I'm not sure how long the logarithmic translation holds up; I've been doing some reading online, and haven't found satisfactory information. It isn't as simple as 2x to 4x, but that's a start.

This article deals with hydroponics, and includes a discussion on growing lights (very powerful ones; 120,000 lumens). Here's a particularly interesting part:

So think about that: on a clear summer day, you might be taking in 10,000 lumens/sq.ft. But it certainly wouldn't appear to be 10 times brighter than a 1000-lumen light at night. And it would be pretty hard to compare the brightness of standing under a tree in the daytime to a bike light in the dead of night, even if both are theoretically putting out the same amount of light. I'd wager the bike light at night would "feel" much brighter, but that would entirely be due to the contrast of the light to the darkness around it.

Our eyes adjust things over a wide scale. The end result is that you can't add the lumens of one light to another on paper and expect them to sum visually; it's not linear.

I'm off to bed soon, but there's loads of interesting material out there on this, apparently.

Not yet, that I know of. There is an MC-E Dreelight, but it's huge and wouldn't be good for cycling. I'm waiting for one too.

Wow! Medium is total rubbish on your light! On my MC-E light medium is between 'Turbo' and 'High' on my Fenix LD2. Yours seems uselessly low....

A lot of people have hyped these lights on here who seem to have little experience with bicycle lighting. There is still a ways to go until we have an excellent flashlight for cycling, but things are getting better by the year.

A little update with my defective MTE P7. I removed the tail cap, took it apart and found some solder that had split. I fixed it, but it's still not functioning. The light will flash every few clicks when depressing the clicky switch, but will not stay on. This is extremely upsetting :(

My P7, batteries and charger arrived from DX. For those interested in delivery time, I ordered on 11/18, and received the order on 12/05.

My impression at first was an epiphany of sorts, in that did not seem possible that so much light was coming from such a small hand held light. While riding a bike, the P7 gives you the impression that you have a car or motorcycle headlight on, and lights up the road similarly. I consider the medium setting easily sufficient for city driving, and the 'high setting' I consider almost like turning on 'high beams' on a car. I would probably not turn on the high setting on a normal road, for fear of blinding oncoming traffic. For a rural road with no street lights, or an off-road setting, the P7 in 'high mode' seems ideal. My 'night kit' now consists of the following:

Headlight: P7 (5-mode)
Tail light: Mars 3.0
Reflective 3M tape on the bike
Reflective 3M 'blinkie' armband
Reflective orange and yellow vest (I only wear this in the worst conditions)

I feel that one thing I may want to add is a 2nd rear blinkie, which for me will probably be the Mars 4.0, and would completely satisfy me as far as night time visibility.

TR-801 is comparable to L2D. I have both, TR-801 is maybe 20 lumens brighter and more throw-ey, but it is less than half the output of either of my 5-mode P7s.

The L2D is pretty floody, in fact my P7s out-throw it slightly (and my P7s are really floody). The TR-801 is better as a helmet light than the L2D as the spot is a little more intense.

I received my lights from DX in 2 weeks and they are amazing. I mounted the Cree to my helmet, and the P7 on the bar. My riding has been limited to the road, and I can't wait to get in the woods. Thanks to all in this Forum!

TrustFire TR-801 Cree Q5-WC 5-Mode Memory
MTE "P7-D" SSC P7-C 5-Mode Memory 900-Lumen

My P7 (MTE 5 mode DX 12060) took eleven days from order to receipt, and I just got it out on its first ride this morning.

On medium, it's a good bit brighter than my upgraded Minewt USB (U bin P4). On high, it's really, really bright. Mine has a pretty bright hot spot in the center, with tons and tons of spill. I really noticed the hot spot since I had it mounted on my helmet, and it turned out to be at too low of an angle, so it was pointing at the road about 10 feet in front of my bike. I'll have to figure out how to attach it so that it's pointing higher.

I just used a Livestrong type band to secure it to my helmet, but I think I'll have to use the inner tube method instead to mount it farther back on the helmet. I'll also have to pad it with pieces of tube because it did switch modes on me once during the 90 minute ride.

I really wish I'd just gotten the two mode in the same housing, as the low and strobe modes are really useless to me.

P7 = bright, really really bright. By far the brightest light in my group today.

What's the runtime on high?

I ran it for the first 25 minutes on medium and then switched to high for another 65 minutes; never noticed it dimming at all. I've not done a run test, but others have reported 70-90 minutes on high before noticeable dimming. I'm using the 2500mah blue Trustfires.

My sku 16092 MTE has ran 6X now continuously in excess of 75 mins on high (4 of these were 83-86 mins, also on high). It was probably getting dimmer towards the end but I didn't notice - didn't seem to dim much, really.

Used trustfire 2500 mah, which are probably really only 2000-2200mah.

The DX description of "2800mA current output regulated" is clearly not true. Probably closer to an average 1600ma based on these 6 rides.

I think I'll get a 13060 and use the 3hz mode with a red lens for a tailight. The color produced is actually an orange shade. In side-by-side test using 16092 on fast stobe. it completely overwhelms the 3 PB Super Flashes I've been using. Can hardly see the 3xPBSF looking at them next to the 16092.

http://www.dealextreme.com/details.dx/sku.16092

You know, knock-off flashlights are one thing, but I don't think I'll be shopping DX for these any time soon:

http://www.dealextreme.com/details.dx/sku.17864

Have they always been in this business, or have I not been paying attention?

It's odd that they sell condoms. It's even more odd that they have pics measuring them with those digital calipers.

Anyway, I ordered a P7 (sku 12060), 4 batteries, and a charger on Sunday and they shipped today. Hopefully I'll have something to back up my NiteRider TrailRat in a couple of weeks.

Has anyone mounted this flashlight to their helmet? I'm wondering how bulky/heavy it is. I'll probably mount it to the bar with a lockblock, since I never liked the weight of my NiteRider on my helmet.

http://dealextreme.com/details.dx/sku.12060

I've used a lockblock in an unconventional fashion to attach a Fenix L2D onto a Giro Atlas II. Appeared to work okay, though I didn't ride test it because I chose to use my old PB Blaze instead. Its helmet mount hardware is really slick and solid.

Bruce, I've mounted that light to my helmet using a Livestrong type band. I didn't notice the weight at all, at least when I had snugged up the helmet. At first it was pointed too low, but I slipped a wine cork under the front of the light and now it's aimed just about perfect. The cork is mounted like in this thread.

Which red lens are you using? I've been thinking about doing this for months, but still haven't. I've used 13060 since September on my nightly rides and it's never let me down, so if it's decent with a lens, I might just buy another.

I grabbed the first piece of red plastic i could find for the quick test - a lens off an old cateye tail light, which was wide enough to cover the 40mm diam lens.

Obviously a nice round 41 mm lens would be better, ideally one with threads to fit the flashlight. I wonder if there are any useful inexpensive filters out there in photography world. Hey I think I got a couple that are ~55mm, for the old FILM slr. Maybe I'll try those.

I don't think you'll get a dinotte-like red light regardless of filter you use - the blue component of the P7 lights seems to turn red-filtered light into an orange-ish color. Which is probably OK anyway. And still less then 1/3 cost of a dinotte tail light, with additional benefit that it can be used as a flashlight.

Please let me know if you find anything.

Forgive my ignorance - but if I purchase regulated batteries, I don't need a regulated flashlight, correct?