Cycling lights come in a huge variety of output levels and features. In this guide we'll look at the latest models, how to understand lumens, and some of the newest features such as rechargeable bike lights and bike LED lights.
We've simplified the main types of bicycle lights by breaking it down into three categories: commuting, road and off-road. We'll explain the differences and explain what you should look for.
Output: What are lumens?
Lumen is the official SI unit of measurement that quantifies how much light is emitted from a source in a given period of time - basically, how bright is your light.
Why use bike lights?
Here's James with an awesome guide to some of the best bike lights available right now, and also some handy tips for usage and purpose.
Rechargeable bike lights versus battery power: What are the options?
You can still buy bike lights that run on disposable alkaline batteries, but most of the best bike lights now feature built-in rechargeable batteries.
The most common rechargeable batteries are Lithium-Ion (Li-Ion) or Lithium Polymer (Li-Po). These are smaller, lighter and more powerful than disposable alkaline batteries, making them perfect for bike lights.
Most rechargeable cycle lights charge via USB and some lights even feature a built-in USB connector for convenience.
Powerful front lights can take a long time to charge via USB, so some come with the additional mains charger for speedy charging.
More and more rechargeable lights are fitted with battery life indicators so you're never caught short. These can be small LED indicators that change colour to indicate how much power is remaining.
Bike light mounts: How do they work?
Front and rear bicycle lights feature a variety of different mounting styles and options. The two most common variants are strap/band mounts and clamp mounts.
Most rear lights and safety lights use a strap or band mounting mechanism which you can easily wrap around your seat post or handlebar, often without the need for tools. Because these kinds of mounts are easy and quick to remove, they are ideal for use with commuting bike lights.
On higher-powered front lights, which are typically heavier, clamp mounts are more common. These are more secure, so they can cope with rough terrain and repeated use. Most clamp mounts feature some means of quick-release for the light unit, so you can still remove the light with ease.
What are the best bike lights for you?
The type of bicycle light that you choose will depend on the kind of riding you do, as well as the kind of conditions you ride in. See which of the below categories best describes your riding.
Bike lights for commuting and urban use
If you're riding in a built-up area, and the road or path is well lit, then your main priority should be to make sure you're visible to other road users.
'Safety lights' usually have at least one constant lighting mode, in addition to multiple flashing modes. They also offer higher levels of side visibility; so you can be seen at junctions by pedestrians and other road users.
We've all seen the guy who looks like he's run off with the lighting rig from Dave's Mobile Disco with multiple flashing lights all over his bike, bag, clothing, and helmet. You may think it's a bit overkill, but remember you did see him! Fitting more than one light with a combination of flashing modes will always make you more visible.
The Cateye Volt 200 Xc / Rapid Mini Light Set is the perfect bike light set for when you want to be seen on the road.
One of the latest innovations in the area of commuter bike lights is the Garmin Varia RLT515 Rearview with Tail Light. It pairs up with your Garmin Edge bike computer to alert you to approaching vehicles from the rear. The sensor has a 140-metre range and its rear light can be seen from up to one a mile away - perfect for innercity rides.
The more adventurous commuter
If your commute takes in some unlit roads or paths, you'll want a more powerful front light, so you can 'see' as well as 'be seen'.
Anything over 200 lumens will be able to cast a beam on the road and offer sufficient light to ride on unlit roads and paths, at a sensible speed.
If the terrain is likely to be rough, or you are likely to come across hazards in the road, then you may want something brighter.
The Lezyne Micro Drive 600XL Front Light is the perfect option if your commute takes you on a few unlit roads or paths.
Bike lights for serious road riding
When your riding takes you on unlit roads, at a fast pace, then you need to think about seriously upgrading your lumen output.
A powerful front light is vital to illuminate the way ahead; picking out potholes, rogue badgers, and stray pedestrians.
For this category, we're talking about powerful, bar-mounted front lights - ideally with an output upwards of 600 lumens.
The right selection of lighting modes is also important; allowing you to adjust your light output to your surroundings, and manage your power reserves on longer rides.
The LifeLine Pavo 900 Lumen Motion Front Light offers some new technology - it features motion control, an intuitive way of prolonging battery life which halves the lumen output when the bike comes to a standstill.
Back-up and safety lights for serious road riding
High powered front lights designed for road riding tend to have quite a concentrated beam so you can see where you're going, but not dazzle oncoming drivers. The downside of this is that they can be less visible from the side. To improve your side-on visibility, consider fitting an additional road cycling safety light to the front of your bike. In flashing mode, it will provide you with an extra presence on the road, while it can also be a useful back-up light if your main light runs out of power.
On the rear, a bright safety light will allow other road users to see you from a good distance. Similar to commuting lights, using the flashing mode, and doubling up on these lights, will make you even more visible.
Many high-end rear safety lights are now compatible with aero seat posts thanks to longer and more flexible band mounts.
The LifeLine Aero Beam Rear Bike Light is one of Wiggle's best selling rear lights.
Bicycle lights for off-road riding
Riding a bike off-road, at night, offers a whole new dimension to your experience. Those familiar trails will feel like adrenaline-inspiring new routes as they look a lot different under the cover of darkness.
You need a really powerful front light so that you can spot hazards such as rabbit holes and overhanging branches that seem like land-mines and trip-snares in the dark. Your usual commuting lights won't cut it. They might seem really bright, even on unlit paths, but out in the woods, you'll be surprised by how much darker it can get.
As a bare minimum, you need a powerful bar mounted front light, ideally with an output upwards of 1000 lumens. These off-road specific lights will have a wider beam pattern too, so they can illuminate the whole of the trail in front of you.
High powered off-road lights feature the ability to "toggle" down the light level; so you can light up the world on those technical descents, but reign back the power, and conserve battery life, on those long uphill drags.
The LifeLine Pavo 2400 Lumen Motion Front Light is one of the most powerful, and most popular off-road specific front bicycle lights. It conserves power by automatically dimming the light when you are moving slowly or standing still.
Another option is the Exposure Axis MK7 Front Light. This powerful cycle light has a max output of 1150 lumens and a run-time of 36-hours. Plus, its rugged design, wide light beam, and button-less operation make it ideal for off-road MTB riding.
A heads-up on the benefits of helmet lights for off-road riding
In addition to a bar-mounted light, a helmet-mounted light with a narrower beam will help you to see around corners and spot any additional hazards that might be lost in the shadow of your main light.
The Light and Motion Imjin 800 Onyx will run for up to four hours and offers outstanding performance.
Summary and buying advice
Bike lights have developed significantly in the last few years. More streamlined, rechargeable batteries and LED technology mean there is no excuse for not being able to see, or be seen, at night.
We would always recommend that you purchase a light that will give you a bit more running time than your typical ride length. That way you'll have a bit of power in reserve if you make an unexpected detour, or need to stop for a mechanical problem.
Always carry spare lights so that you can get home if your main lights fail. If you're planning long distances in the dark, look into external power banks to allow you to recharge on the go.