Regardless of whether you ride at night or not, a quality set of lights should be the first accessory on your list. Typically they are measured in Lumens (the SI unit for luminous flux), which indicates brightness but not directionality.
By law you need white front and red rear lights to be legal to cycle at night, they should be visible from 200m. Rear lights often have flash modes which attract the attention of other road users.
Safety
A quality set of bike lights is one of the most important accessories you can buy for your bike. They are not only required by law for night riding but also improve your visibility to other road users. They are also useful in poor weather conditions, especially when drivers don’t expect a cyclist.
Make sure that you use a white front light and red back light. This is a legal requirement in most countries. Also, be aware that your lights should not be positioned in such a way that they dazzle or confuse other road users. It is also a good idea to use a flashing mode rather than a solid light, as it will attract attention without distracting other road users.
Some bike lights come with hard mounts which are more secure and will hold a larger light better than soft mounts made of stretchy elastic or silicone. Some also come with both types of attachment so you can choose what works best for your bike.
Style
Bike lights are a legal requirement for cyclists after dark, and are important to ensure you can see where you’re going and that you’re visible to other road users. A good bike light will be visible from at least 200 metres and should have a white front and red rear. They should be angled down to prevent dazzling other road users and distracting them.
Modern lights are often svelte and compact, with sleek designs and a range of modes to suit different environments. One option, the Thousand Traveller Light, combines a conventional rear light with two lateral ones for added visibility. This innovative design is backed up by a powerful battery and an easy-to-use interface.
Some lights feature hard mounts that are attached to a permanent location on your bike while others have flexible attachment systems. This allows them to be removed and re-attached easily and quickly. It also means they can be shared between bikes and different users.
Function
The lights you choose for your bike need to be bright enough to illuminate the road. The brightness of a light is measured in lumens. This is a measure of the amount of light output, but can also be a good indicator of how focussed or wide the beam is, and whether it’s a constant or flashing beam. You can compare lumens between lights to determine which has the brightest output, but a more useful measurement is lux, which gives the illuminance of the beam at a standard distance right in front of the bike. Some manufacturers provide this data for their front lights.
Price
Lights are a must for any bike, whether you’re riding after dark or just want to be seen by other road users. Many countries have laws requiring riders to use lights, particularly when riding on roads. The simplest lights will have enough power to make you visible from at least 200 meters, but more powerful models can provide huge light beams for pitch-dark country lanes. The key thing is to understand what your needs are and what features are available before making a decision.
There are two basic types of lights: fixed and removable. Fixed lights are mounted permanently to your bike and take up valuable handlebar space. They are less expensive than other options, but they can’t be used with different bikes and cannot be easily removed and carried. Removable lights are a better option because they can be easily shared among family members and moved between bikes. They also require no special mounting hardware.