Lights

no need, it's already one of the most popular lights* on here*

I came here to talk about mine actually...I had to do some maintenance.

Bought a replacement one of these for my Moon Mask:

Any ideas?

this arrived. slow shipping and no little screw included. 5/10.

Dulwich Dynamo

what's that?

The Dulwich Dynamo was a pub crawl around Dulwich that some people did years ago, based on a joke similar to that of the Dalston Dynamo.

I'd be well in for that

Pubs>>cycling far

Noticed that this morning.

Is the Sirrus decent on unlit country roads (take me home)?

Sorry just realised you asked me a question, no idea on that light mate only have the flash/flare combo.

Ha no worries. Decided to pass.

The cree u2 light that I ordered for £15.50 arrived a couple of days ago. I charged the battery pack, it didn't explode. Good start.

Thought I'd see how it would fare. Sparked the light up on the lowest setting (which could still be described a Pretty Fucking Bright), expecting it to be dead within 4 hours. 4 hours went by, and the three lights on the back we're still on. Went to bed. Next morning: still going. A little dimmer by this point, and on one light, but still, amazing.

I lucked out with a 6 cell pack, so it must/is probably a 8600mAh one.

Runs quite warm, but this won't be a problem when I'm whipping along towards Dunwich.

Impressed. I'd still be impressed for £30, but given it was only 15....wow.

Anyone produce a really simple rear light? one solid mode, not super-bright?

I rate (and use) that long Cateye one, with 5 LEDs I think, less than 20 quid

I'm getting confused by all the claimed battery capacitites of these ebay lights. They are universally powered by a number of 18650s. Generally set up in pairs to give ~8V. Stated battery capacity of 18650s are 2200-3400mAh according to Wiki. So I bought a light which stated it had a 8800mAh battery capacity, and it came with a 4x18650 battery pack. To give a voltage of ~8V, they must be in a 2x2 circuit, i.e two parallel pairs of two batteries in series. My understanding is that this only gives you a capacity of 2x that of one cell. so 4400-6800mAh. Did they just do their maths / science wrong and think 4 cells = 4x capacity -> 8800mAh? Or could they be higher rated cells? I guess the best people to ask is the seller...

Does anyone have any experience with the top-end Exposure lights? How do the road-going light models compare with the MTB ones?

ie. Maxx-D/Six-Pack versus Toro/Strada

I have a Six-Pack and wonder if I'd be better off with one of the road-specific models?

The mtb ones are brighter and illuminate a wider area. From what I understand the road ones are easier to direct in order to light up the ground in front of you without blinding drivers.

I figured they'd be more focused. Do you know if they have a longer beam 'reach' though?

I have an Exposure road light, the Strada, and think its awesome. By far the best light I've ever used and its dim switch is handy, mine came in the set, but if you buy the light only it's worth getting the mode switch.

I can't compare to MTB versions as I've never used one; but, it lights up my side of the carriageway and enough of the hedge and other side for me to know what's there but without flooding it with light that could be used to see where I'm going.

In conclusion, an excellent light.

Cheers, I'm kinda after a comparison though since I already have a stupidly good mtb light of theirs but I'm wondering if the road beams would throw longer than the mtb ones. Burn time seems similar but I'd probably need to use both to decide myself.

I've got a Toro Mk5, can't make a direct comparison but it's crazy bright and illuminates a wide area on it's 2-hour mode. Exposure have some photos you can compare on their site, but they're quite small and look pretty similar for most of the bigger lights.

I'm getting confused by all the claimed battery capacitites of these ebay lights. They are universally powered by a number of 18650s. Generally set up in pairs to give ~8V. Stated battery capacity of 18650s are 2200-3400mAh according to Wiki. So I bought a light which stated it had a 8800mAh battery capacity, and it came with a 4x18650 battery pack. To give a voltage of ~8V, they must be in a 2x2 circuit, i.e two parallel pairs of two batteries in series. My understanding is that this only gives you a capacity of 2x that of one cell. so 4400-6800mAh. Did they just do their maths / science wrong and think 4 cells = 4x capacity -> 8800mAh? Or could they be higher rated cells? I guess the best people to ask is the seller...

Having taken one of the 4 cell packs apart they are configured 2 x 2.
I would say that the maths are correct in that the total battery capacity is 4 x 1 cell mAh. They are standard capacity batteries. i.e around the 2200 mAh range.

I've got a Toro Mk5, can't make a direct comparison but it's crazy bright and illuminates a wide area on it's 2-hour mode. Exposure have some photos you can compare on their site, but they're quite small and look pretty similar for most of the bigger lights.

I know, they all look the bloody same! Compare the meerkats was betterer.

The pictures are bigger here... http://www.use1.com/exposure-lights/lights-comparison

Does show slightly bigger pictures, the Six Pack/MaxxD do look like they illuminate further than the Strada, the Toro being about the same distance but brighter.

Looking at the Toro/Strada, the Strada seems to illuminate a bit wider (close fenceposts) than the Toro too.

Having taken one of the 4 cell packs apart they are configured 2 x 2.
I would say that the maths are correct in that the total battery capacity is 4 x 1 cell mAh. They are standard capacity batteries. i.e around the 2200 mAh range.

But if you put two batteries in series, you get twice the voltage, but the same capacity no?

There is a site that compares lots of lights with pictures for illumination distance and beam profile. I can't recall what it is but it has been mentioned on here before.

Having taken one of the 4 cell packs apart they are configured 2 x 2.
I would say that the maths are correct in that the total battery capacity is 4 x 1 cell mAh. They are standard capacity batteries. i.e around the 2200 mAh range.

But if you put two batteries in series, you get twice the voltage, but the same capacity no?

An excellent intro to 18650 cells, their performance vs the capacity on the label, and a warning about "recycled" cell not marketed as such

Battery configurations are described as *{x}S{y}*P, where xy is the total number of cells, x is the length of each series and y is the number of series connected in parallel.

The series length determines the battery voltage, whilst the number of parallel sets determines the capacity at battery voltage

tl;dr:

Your 2S2P battery should be 4400mAh at (assuming LiCoO2 chemistry) a nominal 7.4V, providing 8.4V when fully charged and 6.4V in a "sensibly empty" state.

Running 18650s down to 3V per cell is possible, but you don't gain much runtime (pretty much falls off a cliff at 3.3V), and Li-ion rechargable batteries provide more total runtime over their lifetime if you recharge at about 20%.

You'll also get better runtime and more chargecycles by not running them too hard. Operating current (and charging current) is normally expressed in "C"s, where running a 2200mAh cell at 2200mA current is a 1C rate. Given a hypothetical LED lamp rated at 20W with a buck driver configured to supply the LED with constant current given a 6-9V input, you would need 2S to provide the necessary voltage, but with only 1P your cells would be pushing about 3A, or about 1.5C. With a 6-cell battery, 2S3P, each cell would be running at 1A, 0.5C.

The test results in Torchy's article(^) show 90%+ of rated capacity for good 18650 cells at 1A.

Batteries for RC models can be rated at up to 90C constant, but you wouldn't expect them to last many charge cycles

There is a site that compares lots of lights with pictures for illumination distance and beam profile. I can't recall what it is but it has been mentioned on here before.

That would be pretty useful assuming it's a 3rd party doing the testing. Any idea/hints about who might've done it?

Looks like I TL'd my tl;dr.

It was a third party. I've found it, http://road.cc/content/news/97193-big-roadcc-lights-test-2013.

I haven't had chance to check which lights it covers though.

I just got a message back from the ebay seller saying "I didn't send the wrong battery, it'll run for 3hrs on "high".

So no answer to my question about actual battery capacities. There was no details about runtime in the product description.

This is annoying as my girlfriend needs the light for L2B night ride at the weekend, so I can't really ask for a refund now. I guess the 4 cell battery should do for the few hours that we'll need it, just annoying to be sold the wrong thing.