Lumen is a measure of total visible light emitted. It can also be written as lm . Nowadays all the bike night lights are measured in terms of lumen. The stronger the Lumen , the stronger the brightness. In older days we called lumen as Watts.
Lumen would be equivalent to the light emitted of full moon in clear sky. Similarly smartphone’s backlight will be equivalent to around 18 – 25 Lumen. A car headlight would bright as 1200 Lumen. In terms of Bulb, a 40 Watt Bulb is equivalent to 450 Lumen of light.
60 Watt bulb is equivalent to 800 Lumen of lights.
Lumen on general is referred to as the light output which actually is not the only parameter to qualify the quality of the emitted light.
In cycling terms there is another word called Lux which in conjunction with lumen can help to determine the quality of the light.
Lux is a surface area where the light is spread.
How much Lumen is needed for bike light ?
Answer depends on what conditions you are riding the bike.
In standard terms :
In daytime ride it would be good if the bike lights are above 100 lumen.
In a Rural ride a good lumen would be of around 400-600 Lumen.
Similarly in day time urban commuting will require around 50-200 Lumens of light.
As per Australian Road Rules, you must have a white light flashing or steady on the front , a red light flashing or steady on the rear light and a red reflector on the back.
Best bike lights for night ride
In night bicycle rides , one might need above 1800 Lumen. We actually have reviewed new 1800 Lumen Bright Eyes Rear Light . If you are looking for something which is cheap bike light then please check our previous posts on bike front lights and bike rear lights the review and features .
What to consider before buying Bike light ?
There are various factors to determine what right night light to choose for the bike.
One of which would be to choose a narrow beam pattern which will not dazzle any oncomers.
We have covered this extensively a buying guide on bike lights.
You need to make sure that a bike will need a brighter front light and mediocre lumen rear light.
Best Off Road Riding Bike Lights
Riding off road bike is always adventures and a bigger challenge which gives a whole new dimension for your ride. Even familiar trails at night are risky and misguided , if right lumen bike light is not chosen.
Hence we always recommend to have a brighter lumen night light , which can easily spot the hazards such as rabbit holes and other obstacles.
If you are riding off road , then best bike night light should be at max 1000 Lumens or greater.
On a general one should make sure the battery Life of the light. Do note , the higher the lumen more fast the battery will rinse.
Its always good to use rechargeable batteries for these lights.
Bottomline , we would always recommend you to buy a light which is more powerful in light emmitance (probably higher Lumen , again depending on situations) and a must look for battery life. With higher battery life, the light will be running for longer period for your bike ride length.
In addition to above , it is always a wise to carry spare lights which will come handy once the main lights are stopped working . If you are riding for longer period , do keep power banks with you to charge the batteries on go.