Don't bother, you are wasting your money, it will still come out pretty white. You need red LEDs.

I have started two threads on that topic, if you are willing to go the DIY route.

http://www.bikeforums.net/showthread...557&highlight=

http://www.bikeforums.net/showthread...641&highlight=

I'm preparing an order for a P7 flashlight from DX right now. planning to get the MTE SSC 5 mode P7
http://www.dealextreme.com/details.dx/sku.12060

plus 18650 charger and batteries. Im planning to mount it parallel to the top tube. I was wondering if anyone has confirmed that the longer protected cells can fit in that particular p7 flashlight.

NEVERMIND. i answered my own questions. i found a pair of protected ones that someone has confirmed to fit.
http://www.dealextreme.com/details.dx/sku.5790

If anyone is interested, I have a charger and protected lithiums from deal extreme. I am sick of waiting for my P7. I commute and the wait has severely cramped my style. I would like $23.00 for the set, including shipping.

01251 UltraFire 3.6/3.7V Battery Charger
05790 TrustFire Protected 18650 Lithium Battery (2500mAh 2-Pack Blue)

If you let me know tonight I can drop it off at the post office when I head over there tomorrow. It will get to you faster than Dealextreme can get it to you, if I walked it to your house. seriously

Once they actually ship, it takes about 9 days. The bigger delays are in waiting for particular lights to return to stock. That's why ordering quickly's a good idea. It took me about three weeks before I finally got everything, but half of that time was spent waiting for DX to get the light itself.

What's the best p7 model? DX has 19 models listed.

http://www.dealextreme.com/search.dx/search.p7

I'd recommend getting one with at least high, medium, low, a strobe, and voltage regulation. I got the 8-mode because a.) it looked the nicest, and b.) it was regulated, and c.) it had eight modes.

So far, I've only used high and high rapid strobe when riding, but I like having the availability of the other modes. I use high rapid when riding off campus in the daytime, as it's the most attention-getting mode on the light.

So if I were buying another light, I'd buy the 8-mode again. It has the most modes, it looks nice, and it's regulated.

I've had my P7 for enough time to test it out. I would not want to be without it. I got the 8 mode because it is regulated. The charger, while not the best, has been keeping the batteries charged. My Dinotte is now my (reliable) backup.

And what are you guys using to attach it to your bike? Will the Twofish lockblock work?

Took the plunge, P7 8-mode, charger, 2 TrustFire batts, mount. We'll see how long it takes to arrive. I hate waiting ;-)

man..i was going to order a P7 light. ended up also adding the charger and batteries, plus a CR123 everyday carry light, plus those batteries, plus dropin SSC P4 LED for my headlamp, plus a pack of 10 microlights. i need to stop! its like buying bike stuff.

I've got one of those on the way, too. My first from elektrolumens, and I'm really looking forward to it.

Please report on how it is. Thanks!

wayne's flashlights are top shelf but he sometimes get way overextended and usually has delays in production.. The attention to detail and ruggedness of his lights are one of the best qualities.. He also is a master of regulation and his lights usually run much longer than other similar torches..

Something else I'd like to add. I can see no reason for getting the 2 mode light. If you shut off the 8 mode for more than 2 seconds it goes back to the 1st (low) mode. The 2nd mode is high beam. It's not a problem to stay within the hi/lo modes.

I bought a one mode P7 light from DX and have tested it for two off-road mtb rides. Results were fantastic on the handlebar. It puts my 2 x DIY 20W halogen light (handlebar, helmet) to shame. Add a helmet light and it's all you need.

I chose the one mode P7, as I'm only interested in the high mode for off-road biking. That, and I can't to be wasting time cycling through modes.

I don't see how that's possible, unless you simply weren't putting enough juice into them. A single mr11 at nominal voltage is rated at ~ 400 lumens, and an mr16 ~800. Overvolted 20% they're about twice those values.

Those p7s from DX put out 400-600 lumens, right? Even elektrolumens claims only 700+.

Source? I've never seen those sort of figures before. First, MR16 has a larger reflector then an mr11 so the beam is better focused. All else being equal, a 20w MR16 does not produce twice the lumens of a 20W MR11. Second, halogen lamps provide around 15-20 lumens per watt. Third, overvolting by 20% yields around ~85% gain but reduces the bulb life by 90%. So that high end 5000 hour bulb will only have a 500 hour life. Fourth, look at the manufacturer's MR11/MR16 lumens/spread chart for a comparison. Fifth, enough poster on this forum, and others, have already shown that a 3xcree setup beats a 20W halogen light.

Other advantages of the P7 include, less heat, better efficiency, and no cables to snap while off-road mountain biking :thumb:.

Does anyone think we've hit a plateau for high power LEDs using AA batteries? Will it be CR123 or 18650 from here on out, or will another breakthrough keep AA's in the game?

I think Dinottes still use AAs in packs. But since 18650s have apparently been standard in laptops for years now (I had no idea they're what laptop and camcorder packs were made of), I wouldn't be surprised to see them more commonly used in high-end lights.

I've used overvolted mr11&16s for commuting for years, I find them more than adequate. Main problem is efficiency and resulting battery requirement.

I've never used 2x20w lamps because it's overkill for my needs, plus would have too little runtime with the batteries I own.

A mr16 is in fact much brighter than the same (20w) rated mr11. You would know this to be true in a second if you had ever actually compared them. This is the main reason why DIYers use mr16. MR11s aren't as bright, they're hard to find, and significantly more expensive.

I don't see how you could be using 2x20w mr16s, overvolted, and have the resulting illumination pale in comparison to an inexpensive p7 flashlight.

I sincerely hope I'm wrong, since I'm all for inexpensive bicycle safety enhancements. Either leds have taken huge leaps in the last year, or you have some crummy mr lights.

I don't read this forum regularly; I'm not obsessed with bike lights. If you have beamshots comparing 2x20w mr lights to a p7 emitter, then please kindly post them or direct me to them by link so that I might evaluate them myself.

BTW, MR16 bulbs cost 2 bucks at lowes - lifespan, cost - it's trivial. 500hrs=5000miles.

I've used the website below occasionally for ideas, and have based decisions and comments on the data presented there. It may be inaccurate. If you have better information, please share it.

http://nordicgroup.us/s78/

http://nordicgroup.us/s78/wattslumens.html

Now that's getting personal. You may ignore my post, or this thread if want to.

Lumens, no. Lux, yes. The bulbs are the same. The larger reflector of a mr16 is better at capturing the light and focusing it then a mr11, hence higher lux. A mr11 has more leakage of light then a mr16.

LEDS have taken huge leaps in the last 2 years.

That site is outdated and the information is inaccurate. First, According to their own source, halogens emit 18-22 lumens per watt. Which is very different from the numbers they list. Second, even a wiki search shows it to be otherwise. Luminous Efficacy. Also check a physics textbook and they show different numbers. Third, according to the lighting research center,

Lumen output:

Most lamp manufacturers do not publish lumen output ratings for MR16 lamps or other reflectorized lamps in their catalogs. Instead, they publish beam angle and CBCP, which provide more accurate information about the performance characteristics of the lamp. NLPIP tested several 50-watt MR16 samples of the same type (EXN) to determine their lumen output, which ranged between 560 lumens to 710 lumens, and averaged 625 lumens.


Now that's for a 50W halogen, imagine what 20W halogen would be rated at (averaged 250 lumens).

For accurate information check this site. It contains a wealth of information on lights including leds, halogen, incans, h.i.d., etc.

I think we've got to take people's visual observations at their words. No matter how good a light 'should be' on paper, all that really matters is what you see in front of you. I'll take a first hand account over a theoretical one any day when it comes to this stuff.

Is there a specific reason that the 8-mode is so often recommended here? It's out of stock so I was thinking about getting this one that has 5 modes.

Probably because the 8-mode model has higher ratings at DX, it claims to be regulated unlike the 5 mode model, and has a copper heatsink. Though, both models are fine.

Also the mode sequence are different. For the 8 mode, it's "Mid > Hi > Rapid Strobe > Low > 3Hz Strobe (Alert Mode) > 1Hz Strobe (Alert Mode) > SOS > Special Tactical Police Style Strobe". For the 5 mode, it's "Lo > Mid > Hi > Strobe > SOS". It might be preferable to start with the mid mode instead of the low mode (which may be too low).

Is there a good option with two AA batteris. I have tons of them and prefer
to not get another charger and start another battery collection.

I do two have a Fenix L2D Premium Q5 . My issue is that the 180 lumens is in the strobe mode and the 100 is in the steady. I love the strobe for people to see me, but a steady light will help see the road better.

Thanks

You are mistaken, it's also 180 lumens steady in 'turbo' mode.

How is the throw on the DX 8 mode p7?

Most P7 flashlights are more floody which is ideal for bike riding.. If you want great throw look at the Fenix TK11 - Q5 light..