Interesting. I wasn't aware of this effect. However, my second question would be, is it possible to patch something like this into a Panasonic hub-drive bike without invalidating the warranty? For me, anyway, I'm thinking that separate battery lights are still the way to go. For most other ebike owners though, I'm sure you're right - run them off the main battery.
(Duh!).Generally speaking a larger reflector is better able to focus the emitted light into a narrow cone, so an identical light with a larger reflector has more throw. The luminous intensity (measured in lux) is greater in the hotspot. If you are caught in the hotspot then the light with the larger reflector will appear brighter. However conversely if you are off to the side then the light with the smaller reflector would appear brighter; the beam has more spill (light off to the side) and the hotspot is wider so you may still be caught in it. The Banggood appears to have a pretty decent sized reflector so I'd expect it to throw well.
White LEDs through red filters unfortunately aren't very effective or efficient. A white LED is a very pure light and doesn't have a huge amount of emitted power in the red wavelengths. A far less powerful red LED would appear quite a bit brighter.
I've had a good look at those in recent weeks - they do look good. They have just released their latest version the Skyline, which is less obtrusive on the bike. Unfortunately the maximum tyre width is 38mm (they are all 700C diameter) which might rule out quite a few ebikes. Also only the complete wheels (with the older version of Revolights) is available here so the Skyline version would have to be shipped from the US, would incur VAT and I haven't asked them about the shipping cost.
Indeed it should be plenty bright for what is needed. However the light is using 10W of power and a 1W red LED would be both brighter and a more pure red colour. But yes, you'll have ample light out the back to be seen by!
I think that's a bit of a problem though. If they think you're a bike, some drivers will treat you with the normal ignorance and disrespect. Since I've started using bright lights, I seem to get a lot more consideration from drivers.
I know what you mean, but I don't think that's the case here. Something like the revolights is so totally out of the ordinary that it forces its way through people's subconscious and makes them take notice. It's a bit like riding a recumbent - anecdotal evidence suggests they are actually safer in traffic because they are so different to what drivers normally encounter. Their mental autopilot is tracking along - "car, another car, person, car, bicycle, car, bicycle, car, ... WHAT IS THAT!?".
You can always rely on Martin for the, er, gold-plated solution:
They have a UK agent in London
They do, but unfortunately only for the complete wheels, fitted with the older "city" lights. The ones to fit to your own wheels aren't available here.
Martin has found out that some people are happy to pay £2000 for device that kicks you in the nuts when you pull a lever on the bars, so I'm sure he can keep a straight face while they queue up for that light at only £280.
