1x18650 light for bicycle

I need a 1x18650 light for bicycle riding (for a friend).

Should have quite a wide beam, flooding 20 meters ahead is more important than seeing to distances.

Should have good heat sinking - meant for rides longer than an hour. Good battery life is also important, so at least high/medium modes; with low mode is preferable. I don’t care if it has blinking modes.

Should be light weight; preferably water proof/resistant.

Shouldn’t be too modable, would probably not be modded at all.

Preferably from a good quality store - CNQG/IOS/HKE etc., although I can probably bite my tongue and order from DX/FP/MF again.

Price - my friend said 25$, but I think he would prefer a better quality light, so the budget may be stretched to 40$. (but try to suggest at around the 25$ mark)



That should do the job, just get some decent cells, pick your modes and tint and your mates laughing. :bigsmile:

Between rides is the best bet for mount links but I believe he favours the two fish mounts or has links for good replica mounts. Might be worth a pm.

I just got done useing my 501b on my bike had it on low and could see very well in the dark park i just used a cheap holder for it.ha the other night i used my 3 xml t6 light . i got to many complants from it lol

I’d like to try the Xin TD recomended by gords on my bikes but it doesn’t seem to fit what the OP was asking for.

If you want a wide beam, I rode home tonight with a OP reflector 501b found here: http://www.aliexpress.com/item/11-5-Ultrafire-501B-Cree-XM-L-U2-1300-Lumen-5-Mode-LED-Flashlight-Free/473581397.html Less than $10 to your door and seems to meet your requirements. Mine took 3 1/2 weeks to get to Midwest USA.

If you are willing to triple the budget for better quality, no blinkie modes, and maybe a few more lumens you could step up to a Solarforce L2M with the dropin Foy recomends as seen here: http://www.manafont.com/product_info.php/ultrafire-cree-t6-3mode-memory-led-dropin-module-42v-max-p-5178?rp=3611239.

I use the real Twofish mounts as I like the fact that the straps are set up like links of a chain and the block is just to keep the light and bar seperated. The clones are a lot cheaper but I’ve always feared the block could tear with the loss of the light (although I’ve yet to experience that or even hear of it being a problem.) The lights seem to be much more stable when mounted under the bar rather than over it.

Buy the Xin TD and sputter the reflector . It will give the beam more spill and diffuse the hotspot . This treatment has made my Xin TD my favorite bike light .


Are you using the Xin TD mounted on the bars or helmet? I sometimes use both the L2M and 501B on the bars and an xpg s-mini mounted on the helmet. I like the throw and size of the s-mini but sometimes want a few more lumens - how much of a change would I notice if I swapped the s-mini for a Xin TD?

At that price range you’ll be hard pressed to do better than the Ultrafire HD2010


I use the Xin TD on the bar . I don't like heavy lights on a helmet ...

I’ve been using these for the family night time bike rides, they’re cheap, and almost any small/medium light works. Just make sure you place the light UNDER the bar, and balance centered so it doesn’t swivel down or up.


I’ve used my XinTD, a few different 501B lights, an older Aurora SSC P7, and even some smaller AA lights.

My favorite is the XinTD, it has a great throw/flood combo, even without modding the reflector.

I would definitely recommend shopping at intl-outdoors. Specifically because their lights give you the choice of modes and most importantly they have a known good driver. The reason this is important is because when you’re riding a bike slow PWM frequencies can become very distracting. The nanjg drivers have very high frequency drivers that make the PWM essentially invisible.

The Roche F12 driven at 1.75 ought to be very bright and it would definitely be a nice floody light. Definitely more output than an XP-G because it not only is driven .25 amps higher but it being XM-L not fully driven, the output should be great. 20 meters is definitely a doable distance as the XM-L on my Fandyfire 2160, which has similar dimensions, is driven at 1 amp and can almost light up my whole backyard at night.


Heat build up shouldn’t be a problem, just moving through the air on a bicycle should cool it no problem. Also the three modes driver is very nicely spaced. I have the 1 amp version and can tell you an XM-L driven at just .3 amps is plenty enough to ride around with and will last 10 hours on a good 18650.

I don’t think P60 type lights could fit here, their heat sinking sucks and this is a real problem in a hot country like Israel (the flashlight would probably not be used exclusively during bike rides).

The Roche looks interesting, but https://budgetlightforum.com/t/-/10128 shows some problems: the light heats really fast, the body is a bit on the thin side (and I want it to fit the 3400mAh cells which are a bit fatter than normal 18650).

The XinTD looks good, but I think it’s too large and too focused for his needs. But I’ll have to ask him that, looks fine in other areas. (heat sinking, output, I think battery tube is large enough for Keeppower 3400mAh, right?).

Other suggestions?

Trust me, a c8 is not large, your fist will pretty much bury it, I was shocked when I first got a c8 at just how small it is. The head is 40mm, an average Apple or orange is bigger. :wink:

The fact the Roche heats up fast is actually a good sign. It means there’s a good heat path to the air. I have another custom built Fandyfire 2160 which runs at 2 amps and can tell you it doesn’t get unreasonably hot. As in you can always hold it in your hand and if moving, the moving air cools it so nothing overheats. Also the intl-outdoors is underdriven by a good amount 1.75 amps vs the 2.5 amps on the review you linked. So heat will not be a significant problem.

As for trying to fit 3400 mah cells. It may or may not fit. Trust me worrying about the biggest oversize cells seems a pretty useless excuse to try to discount a reason for buying that light. You only get marginally more runtime, and probably no advantage when running high currents like 2+ amps, than a good 2800 mah cell like an AW. The high internal resistance of those high capacity cells makes it so you don’t really get more runtime on high powered lights. And it’s just as easy and a better idea to carry a spare cell and double your runtime. Plus running the light on a lower mode puts out nearly as much light and gets you more runtime than your body has endurance.

The most important thing though that, if you’ve never experienced it, is low PWM frequency. I really can’t stress this point enough. I’m telling you it is very distracting while riding, any fast moving object seem to just strobe while moving and it seems just very unnatural and can even give you a headache. Intl-outdoors is pretty much the only site where you know you’re getting a good very high frequency driver.

A P60 sized flashlight (Ultrafire 501b, solarforce L2 or variants) or if you’re willing to spend a little more get the shadow JM07, preferably with a 26650 battery for run-time, although it works with a 18650 cell.

My first bike light was an ultrafire C8, and personally I think the C8 beam sucks for biking. The hotspot is too small to be practical and pretty annoying. An OP reflector is an improvement, but not as good as an OP reflector on a P60 host or the JM07 IMO.

HD2011 or the Roche F12 are other options with smaller reflectors and are very floody, although my preference is using these in combination with a larger sized flashlight with added throw rather than using them alone.

If heatsinking with P60’s are a concern there are a lot of flashlights out there that have P60 sized reflectors and proper heat transfer. I recently acquired the Shadow VG10 which has excellent heat transfer considering there is no pill, the emitter is attached directly to the flashlight body and at 2.10A it seems as bright as my solarforce 3A flashlights.

The Roche F8’s also have P60 sized reflectors. They may have battery fitting issues so you’d probably want to use unprotected batteries with them. I’m getting the host later as one of my favourite beam patterns for cycling are 2 x P60’s for extra brightness and a good all-round flood and throw beam pattern. The VG10 alongside the F8 would perform even better due to superior thermal transfer, and a couple of 3A drivers just because.


At Int’l Outdoor Store… the EDC 18650 XML at 2.45A…

how does that compare with the Roche?
too hot?
maybe the lower mode is bright enough?

This paragraph made me wtf

  1. 3400mAh cells are not oversized, they are exactly 18mm diameter / 65mm length like every other 18650
  2. “cell like an AW”? WTF? AW doesn’t makes cells
  3. AW’s aren’t any better than loads of other manufacturers
  4. AW doesn’t has 2800mAh batteries
  5. 3400mAh Panasonic cells have lowest internal resistance of all non-IMR 18650’s, what’s with the “high internal resistance of those high capacity cells”? :confused:

Panasonic cells don’t have the lowest internal resistance take a look at this comparison of cells.


Look specifically at the discharge, capacity graph. You’ll notice one thing, it’s readily apparent on cells within the AW brand because they’re comparable to each other side by side based on capacity. We all know the lower capacity 2600 AW cells are monsters when it comes to high discharge rates, ie they don’t sag in voltage under high current draws like their higher capacity cells. This also translates to having the same capacity whether discharged at high currents or low currents.

The AW 2600 cell shows a very narrow capacity gap between high discharge rates and low, this is indicative of low internal resistance. Take a look on the other hand at the Panasonic 3400 cell, it has a very wide gap between the capacity between low discharge rates and high discharge rates, this is indicative of high internal resistance and sagging voltages at high current discharge rates. So your assumption that Panasonic cells have the lowest internal resistance is just plain wrong. Plus this has been confirmed that constantly discharging high capacity cells at high currents leads to earlier failure of the cells. They lose their high capacity if overstressed repeatedly.

AW may not make their cells themselves but they spec for a higher quality cell from the manufacturers, this means less variance in capacity and internal resistance. This makes for higher quality overall and explains why they charge more. And yet when people ask for what’s a good battery to use one of the first brands to come out is AW specifically because they have the least failure rate among other batteries.

As for being oversize, the Panasonic is a bare cell vs a protected battery so it’s not as wide as can be. BUT take a look, it’s a bare cell with an 18.3mm diameter so it is oversize because my Samsung 2600 mah bare cells are 18.1mm. If a battery maker wants to add a protection circuit and the necessary overwrap the cells become oversize.

>So your assumption that Panasonic cells have the lowest internal resistance is just plain wrong.
Internal resistance of AW 2600mAh: 160 mOhm
Internal resistance of Panasonic NCR18650B 3400mAh: 110 mOhm.

If your bike light gets hot , you're moving too slow ...

The Roche is more known for over heating and not taking most cells, the edc linked above is good, I have one and I’ve not found a cell that doesn’t fit. Now, you may say its under driven, but at 2.5a to the emitter, its enough.

I still say the xintd is the light to go for myself, the edc is a great little light, but may not be throwy enough and once you’ve added a couple of dollars for the u2 or t6 3c, your at the price range of the xintd anyway. Both though will provide more light than the Roche driven at 1.75a, I was under the impression the Roche was a 2.8a monster, its probably had the current dropped so much because of the heat issues. Even then though, your still stuck with a light that is cell fussy.