Those who follow the blog for some time know that for shooting at night I use a good front light (I like the light source is directed exactly to where I look).
However, it seems to me that an entry was already necessary on the blog on lighting systems for bicycle, and I bring it in the form of general concepts that we must know when choosing one or another system.
The first important concept is the one referring to the units of measure of the level of illumination. This is measured in lux. A lux is simply the illumination of a surface which receives uniformly a luminous flux of one lumen per square meter. That is, lux is a derivative measure based on the lumen that takes into account the surface on which the light is distributed.
To give you an idea of the matter, the light that allows us to see a clear night full moon is between 0.25 and 1 lux. So, for practical purposes, what light power should a bicycle headlamp have? Well we could put this power in a fork between 40-50 lux (at least) if we plan to roll on roads without lighting up to only 4 lux if we shoot by city or roads with sufficient illumination. This is the difference between having a power to see correctly (or very well) without lighting or simply to be seen (with 4 lux by a dark road we will see very little), a basic criterion when buying our lighthouse.
However it should be noted that the data referred to the lux of a lighthouse is not totally objective. However, if we want an objective, the sector’s industrial regulation has fixed the voltage of the lighting systems for bicycles in 6V and the electrical power in at least 3W.
Halogen Or Led?
Fast response: led light. No doubt they are superior in terms of consumption, duration and power(which does not remove halogen bulbs at good price and good power)
Batteries, Battery Or Dynamo?
This is the big question, and there are answers for all tastes. The first thing we need to know is whether we will need lighting occasionally, often or habitually.
If the use is going to be occasional, the cheapest option is without doubt a battery-operated system, with the advantage that they are usually “take-off” lights that we do not always have to carry.
If we enter a midrange with lights of some power, it is worth the rechargeable lights that are powered by a rechargeable battery , some of which can also be charged via a USB socket.
When we roll with a certain frequency at night, for example in cities where part of the year falls early or if we do cyclotourism anywhere in the world or time of year, we should install a system powered by dynamo.
The dynamo gives us constant, autonomous and always available light. We do not have to think about buying batteries or recharging the battery. In return, we will have a resistance topedaling , variable according to the type of dynamo.
We have two main types of dynamos (I do not enter into others less used): the dynamo of lateral or of bottle and the dynamo of hub.
The bottle dynamo is the cheapest. It takes the energy (I was going to put “take” but I remembered that this blog reads a lot in Argentina ) of our wheel when supporting its rotating head on the flank of the tire. It has the advantage of weighing very little and adapt and install easily on any bike, but in exchange for offering greater resistance by friction, to make some noise and to be able to fail, when skating, in case of rain (although there are tires that have a band of Grooved tread for these dynamos which to some extent avoid this drawback). Although they are less effective than a hub dynamo, they are of high quality and worth paying a little more, because the efficiency of conversion from friction to electricity will be greater (as we illuminate with our effort, that this be used as much as possible ). This is the case of B & M DYMOTEC (perhaps the most interesting option on the market), which promises an efficiency of 40% and has the head roller interchangeable.
The bottle dynamos are sufficient for a non exhaustive use, but for a very frequent use, the most suitable is the hub dynamo (although I think it would be more correct to speak of hub with integrated dynamo). This pulls the energy out of the wheel ‘s own turn as it is integrated into the hub. The great advantage is that it does not offer frictional resistance (although it is, albeit minimal, the very electromagnetic phenomenon that generates electricity), it does not make noise, it works in the most adverse conditions of rain or mud and it does not have maintenance. On the other side of the scale is the fact that they are heavier (something that personally does not seem important to me), much more expensive and you need to completely dismantle the wheel to install them, since you have to replace the bushing, something that is not Within reach of anyone. So, either we buy the dynamo bush and we take the wheel to a workshop to be replaced, or else, most commonly, we buy a complete wheel with a hub of this type.
One factor to keep in mind is that the hub dynamo, although we are not using the light, will continue to offer resistance (although it is almost negligible, so we have to relativize this point a lot), while the bottle simply decouples from The wheel when we do not use it.However, hub dynamos also have the advantage that they can be used to charge other devices , for example, the mobile phone or a GPS.
It is interesting to mention that if we decide for a dynamo, we also choose a headlight with condenser , a device that allows to store enough energy so that the light does not turn off when we stop or we roll very slowly.
Personally, the decision to opt for one type of dynamo or another I think is mostly economic.In the case of choosing a hub dynamo, already involved in expenses I think it is worth it to be of quality (although of course there is no reason to reach 200 euros and peak of a high range).