niggle wrote:Been wondering about Reelights actually as an 'always on' solution. Not sure how bright they are though?
I have Reelights. For those who are unfamiliar with them, these are a no-battery LED light that is powered by the motion of magnets fitted to the spokes. You can get them with a capacitor to stay on when you stop, but they won't stay on very long if you are stopping frequently, and the max is about 90 seconds.
Personally I would recommend fitting some such light to a bike as a day running light and back-up night light, particularly for teenagers who are inclined to be forgetful and find their detachable lights lost or not working. But you should normally have a second lighting system for when it is dark, and the Reelights are a get-you-home solution when the main lights aren't working.
They are really pretty bright when they are working. They are bright enough that the fact that the front light "leaks" some light back into my eyes results in annoying loss of dark acclimatisation on a dark night. Perhaps I ought to tape it.
I use them as a subsidiary light, ie, when it is actually properly dark I use a battery light as well. They will normally "get me home" if I have had an accident with the battery lights, but it is quite difficult cycling on a dark road with nothing but them. However there are also reasons why I would not wish to use them as my main light when it is actually dark, and there are also difficulties with the design. I do not know to what extent the unreliabilities I suffer with them, especially the front lights, is some isolated faulty manufacturing or a general problem.
The main problem with the design is that the magnets are strong enough to cause the arm the light is on to deflect towards the magnet. This is a problem at lower speeds of cycling. So although they tell you to set up the lights with a gap of so many mm, (I forget the precise number) in practice at such a small gap the arm will deflect sufficiently to strike the magnet at low cycling speeds. So you have to set them up with a larger gap, and then there is less power to make them nice and bright at lower speeds.
I have two sets of the lights, and with both of them I find the front light seems to need more power and the capacitor lasts less long. I find that they work less well when it is cold. On one of them, the capacitor stops working when it is cold. In fact it didn't work at all for the first 6 months or so and then suddenly started working when the weather warmed up. I also found that one of them decided to stop working at all below about 15km/h last winter, and then once the warm weather arrived randomly decided to work perfectly again.
But even when they are working perfectly, the front lights are a bit of a liability on steep hills when 4km/h can be insufficient to light them, especially with the widened gap to avoid striking the magnets at low speed.