Bike with gleaming bike light at night

How to Choose Your Bike Lights

It’s important to make sure your bike is properly kitted out for those darker mornings and late evening rides.

Whether it’s to guide you down a dark country road or to stand out in the mayhem of a bustling city centre, you’ll want the right bike lights for the job.
With more and more people taking up cycling, it’s important that we are all aware of the importance of proper lighting.

Close-up of a bike light in daytime

Choosing The Best Bike Lights For Each Season

Bike lights for spring/summer

Those unusually long British summer days mean that many of us rarely ever need to think about lights on a bike from May through August. Traditionally it has only been the few hardy souls among us, the year-round commuters and the competitive cyclists clocking up the winter base miles who need to think seriously about lights.

red bike light attached to seat pole

Bike lights for autumn/winter

When the clocks change by the end of October, it may be dark by the time most people finish work. For the safety of all road users, it is important that we make an effort to select the best lights for our needs.

Therefore, you'll need to ensure you have the right type of front lights and back lights, so you're easily identifiable to motorists, pedestrians and other cyclists. These vary from USB rechargeable lights to battery-powered lights - all of which will emit different levels of light (measured in lumens).

The Law Regarding Bike Lights

A quick summary of what’s legally required

In the UK, it's illegal to cycle on any public road in the dark without lights and reflectors. If you're unsure which lights and reflectors you should use for your bike, it's a good idea to check out the UK's Road Vehicles Lighting Regulations.

The Road Vehicles Lighting Regulations state that you must use lights and reflectors on a pedal cycle when you're riding after sunset or before sunrise. These must be in good working order - and as long as they're clean and do the job, you'll be fine in the eyes of the law. However, to ensure maximum visibility and safety, you’ll want to go a step further and find the right lights based on your needs.

The Dangers Of Cycling At Night Without A Light

Without a bike light, you’re at serious risk of not being seen by other road users. Drivers are human, some speed and become distracted. Accidents can happen. Without a light you tend to blend into the surroundings, making the chances of a mishap all the more likely. Outside of well-lit town and city centres, you’ll want more powerful lights on those dark country roads. Potholes and uneven surfaces can easily throw you off.

close-up of red bike light in front of city lights

Choosing The Right Lights For Your Bike

The first thing to consider is the lumen rating of your lights...

A bike's rear light will emit anywhere from 5 to 100 lumen, while a front light can be as dim as 10 lumen or up to several thousand lumens, but what exactly are lumens?

  • bike light illuminating white light

    What Are Lumens?

    A lumen is a unit for measuring how bright a light appears to our eyes. The higher the lumen value, the brighter the light. Some lights can be as dim as 5 lumens, while bright sunlight can have an illuminance of 100,000 lumen per square metre!

  • red bike light

    How Many Lumens Do You Need?

    This will all depend on when and where you cycle. If you frequently ride in rural areas or dark paths at night, you’ll need a brighter front light. On a well-lit urban road, however, a very bright light could distract other road users, so it would be sensible to go for something with lower lumen.

  • bike light attached to handlebar

    Appropriate Lumen Range For Different Environments:

    Cities: 20-200 lumen

    Rural areas: 200-800 lumen

    Remote trails: 800+ lumen

a man fitting his bike light on to a bike

Fitting Your Bike Lights

Normally, you'll fit battery-powered front lights just above the handlebars, although you may prefer to fit them below so you have more space. Fit your back lights to the seatpost, although make sure they're not blocked by any clothing or baggage.

You can fit rear dynamo lights on the rear carrier/mudguard, while dynamo lights must be securely bolted to the fork-crown to keep the wires away from the handlebars.

a man adjusting his bike light

Batteries For Your Bike Lights

Always make sure your light battery is fully charged, even if you’re only planning a short journey. Also, for regular cyclists, it may be worth carrying a spare, as it’s inevitable that your light will suddenly decide to stop working just when you need it most.

An advantage of running a USB rechargeable light is that you can recharge it anywhere where you can connect it to a USB port - and the battery will last for several hours. However, battery-powered lights are generally cheaper and have a much longer continuous/flashing mode - so you won't need to charge them as frequently.

red bike light in front of illuminated city lights

Stay Safe, Stay Seen

The winter days may be short on light, but don't let that stop you from cycling. The hardy among us can safely enjoy the benefits of winter commutes and training rides by mounting suitable bike lights.

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