While I think neutral tint is nicer, I dont use neutral lights on my bike.
When I'm on my bike, I want as much light as possible, and neutral tint takes away lumens.
I don't own a KD C8, but i have read great things about it...but it looks as if it would be too big for pocket carry.
It would probably make an awesome bike light though.
After I’ve thought too hard about which flashlight to order I opted for 504B because of the seize.
Non-18650s can’t be pocket carried while giving the same light.
Is there any alternative to the 504B with regard to light outpue an also to price, maybe with 2 18650?
The flash light should fit at least into a bigger side pocket. I don’t want to wear a holster even if such lights have a better throw.
Are there any flashlights with 2x18650 and XP-G R5 or XM-L (why under-driven?)? Or isn’t there such a big difference to 1x18650?
Thanks for linking this XTAR deal. I’m already following this XTAR group buy.
I just want to let you know the last couple people that bought the 504B had trouble fitting the Xtar batteries in them. I have 4 504Bs and I love them but I do not have any Xtar batteries I use the Trustfire flames or the Samsungs. I just want to save you the trouble of ordering this stuff and waiting weeks only to find out they won't work together.
Thanks for your replies.
So the XTAR 18650 has some bigger diameter as standardized?
Where can I get the Trustfire flames and an Euro charger at a good price?
I have seen this Solarforce L2 before. But this flashlight also is only 1x18650.
Is the L2 better than the 504B regarding light output and build quality?
L2 has XP-G and 504B has XM-L. I think the XM-L is the better emitter.
But both flashlight are onlyy 1x18650. Are there any interesting 2x18650 models - which are better, but at the same time not so much more expensive?
This are good 18650 batteries and charger I have both and recommend them they work good.
http://www.dealextreme.com/p/trustfire-tr-001-multi-purpose-lithium-batt...
http://www.dealextreme.com/p/trustfire-protected-18650-3-7v-true-2400mah...
I have this 504B light and it is really good quality it pulls over 3 amps on high with the batteries I recomended so 8oo lumens is about right.
I do not recommend to buy 504B from DX now :) I can compare two samples - one bought in march and one ordered about month ago. Older one fits all batteries well - XTAR 18700, blue trustfires, black trustfires... Is even brighter and came without any scratches. That new one is a bit junk - dropin and reflector is a bit different, some scratches on body, and it is impossible to fit almost all blue trustfire batteries (from 4 ONE fits), black trustfire battery fits tight :)
Okay, so should I go for Solarforce L2 as bulid quality is better and consistent? Or any alternative? But no 2x 18650 flashlights?
The L2 comes "only" with a XP-G. But isn't the XM-L emitter the one which delivers more light?
So should I take into consideration to mod the L2 later? Is there a fitting XM-L emitter available?
you could consider http://www.lightake.com/detail.do/sku.L2_Flashlight_Body_Tube_with_Extension_Tube_Silver-30640 with http://www.kaidomain.com/ProductDetails.aspx?ProductId=11106 -mine was too cold, so I replaced the led with t4 (lots warmer and nicer)
colder tints are better for beeing seen but warmer (or neutral) leds make you see better
it isn't that much powerful, it draws ~2A from 18650 and ~1A from two 18650
and my hi-max cells fit without a problem (nie je to na picu ako tvoja, patrik :D )
The post you linked is a picture of Simplemans 504B he bought from Manafont not from DX and the over sized batteries he used XTAR18700s do not fit a lot of lights there is no problem with Simplmans light and he did not buy it from DX so I a not sure what your point is.
I would really like to see your picture of your 2 samples because my 4 504bs are all the same 2 from Manafont 2 from DX all purchased at different times over the last 6 months all identical all work with Trustfire 18650 flame batteries.
The DX drop in I got in May has changed it used to be limited to 1.4 amps on high the new one pulls over 3 amps on high so it is better than the old one I bought in January. So I stand by my recommendation and I would really like you to post some pictures if these alleged defects.
Please post pictures of your DX lights as mine are all identical four samples from 4 different dates 2 different suppliers all identical.
A lot of people on here have reported problems with Lightake including them spamming the sight repeatedly so i would avoid that site.
L2 body with extension tube? Is this from Solarforce or at least a clone with a good build quality?
The XM-L emitter generally isn't that powerful? Or are you talking of the T4? Is the XP-G the one with more power?
Do I understand right that the only difference between 1x and 2x18650 flashlights is the run time? There is no difference in the light output?
504B still an alternative? But where to buy to avois a flop?
E1320 - I did not say that s1mp13m4n has that body from DX, but it has the same problem like newer 504B (1-mode) that I bought for my friend 
I do not own that light right now, but I can write about it: newer one looks like they advertise http://www.dealextreme.com/p/ultrafire-wf504b-xm-lt6-510-lumen-white-led-flashlight-with-strap-black-1-x-18650-57097 . Older one (ordered 19.3.) has smaller hole in reflector near LED, red PCB on drop-in and reflector look like "more textured" 
the one from lightake is a clone (504B?) with a nice shiny finish :)
xm-l is powerful, about 50% brighter than xp-g.. just that dropin with 18V max isn't driving it to the full potential, which is not bad (considering the heat sag in p60 dropins)
I can have my fake L2 short (~1+ hour of runtime) or long (~2+ hours of runtime) and it is the same brightness
oh and it is fairly waterproof ;) 
I have neutral white xm-l t4 (bin) 5a3 (tint) from cutter
But the XM-L driver with 18V max is still brighter than a XP-G?
So this is what Be-Seen Triker meant with under driven XM-L?
18V max is good for longer run time and also for longer last of the emitter beacuse of the reduced heat (btw how long will the XM-L last in this configuration?), right?
Well, 1 hour at max power shall be sufficient. How many modes does this XML T6 dropin have and what will be the run time in medium/ low mode?
Is there a clone body for 1x18650, also or should I directly take the original L2 body then?
And waterproof is a very useful feature for biking!;)
Here are my 4 504Bs all excellent quality. I cannot tell them apart they are all identical. I bought 2 from DX and 2 from Manafont the newest one I bought was from DX in May with the 5 mode XML drop in it pulls 3.5 amps on high about 800 lumens with the Trustfire flames from DX. This would be a great combination for a biker.
I cannot guess what the problem was with Patricks sample but I can tell you mine are all of excellent quality and I think it is safe to get one from Manafont or DX as long as you don't try and fit the Xtar batteries in them.
E1320 - so it is normal that Xtar batteries will not fit? Then the newest sample is not junk but OK and that older is "special" Here is video with XTAR 18700 2600mAh http://vimeo.com/26715338 (on right in "more" is older video with blue trustfires too...).
A lower voltage XML should still be a little brighter than a harder driven XPG light. Here is a link that is helpful determining brightness.
http://flashlight-wiki.com/Brightness_Bins
You can calculate approximate runtime this way the Trustfire is rated at 2400mah that means at 2.4 amps draw on high it will run for an hour, at 1 amp draw on medium 2.4 hours or low .15 amp draw about 16 hours. These are approximate numbers battery makers mah numbers tend to be exaggerated and amp draw varies from light to light
Triker was referring to the high voltage drop in only delivering 1.5-2amps on high instead of 3 amps that most low voltage drop in deliver. The advantage of the high voltage drop ins are that you can use more batteries 2 or 3 to get more run time. I prefer the low voltage ones and I just carry a spare battery with me instead of in the light.
Patrik I don't know what is different about these new lights mine are all the same the only thing I can see different is the Xtar batteries are oversized. I don't know that they changed the lights mine are all identical and I have not seen any proof that they are delivering different versions of the 504b from Manafont or DX.I am sure there are cheaper versions of this light being delivered from different venders but I have not seen pictures or measurements that prove DX or Mananfont are delivering the cheaper ones.
Thanks for your explanation.
How is high and low voltage defined?
The 504B comes with a low voltage drop-in, right?
I'm of the same opinion to carry a spare battery seperately. And a XM-L running with 1x18650 for about 2,5 hours @ medium should be sufficient for me.
Are L2 and 504B also waterproof like the L2 clone with extension tube?
What shall I do now? Order the 504B from DX or Manafont and hope that the flashlight will be delivered in good quality?
Or ordering the more expensive L2 directly from Solarforce Sales?
This is what I have and use and would recommend for a starter kit. I really think you will be super happy with this setup. This is the cheapest way to get the most light.
http://www.dealextreme.com/p/trustfire-tr-001-multi-purpose-lithium-batt...
http://www.dealextreme.com/p/trustfire-protected-18650-3-7v-true-2400mah...
http://www.dealextreme.com/p/ultrafire-wf504b-xm-lt6-5-mode-510-lumen-wh...
$45 dollars for everything you need to get started. You could add an extra pair of batteries for another $10 dollars or upgrade to the Solarforce for another $20 if you want but you won't get anymore light out of it.
High voltage is usually defined as over 4.2 volts which is what one lion battery delivers this would be a low voltage setup. This setup will be completely waterproof and of excellent quality.
Look really good at the picture of the lights I posted that is what DX is delivering right now so I think you will be happy with the quality I am very picky and very happy with the quality of this light especially for this price.
Here is a review of the 504B host.