Extra lights on a motorbike do two things. They help you see further down dark country lanes, and they make you much easier for other drivers to spot, which matters just as much. A bike with a single headlight is easy to lose against a busy background or mistake for a car further away.
The choice of lights is huge, though, and how you wire them matters as much as which ones you buy. This guide covers the main types, mounting, wiring and the rules worth knowing before you fit them.
Spot, flood or driving light?
The beam pattern is the first thing to decide.
Spot beams throw a narrow, concentrated beam a long way ahead. They're great on open roads at night, where you want to see as far down the road as possible.
Flood beams spread the light wide and short. They light up verges, junctions and the edges of the road, and they're useful off road or on twisty lanes.
Combo or driving lights sit in between, with a mix of distance and spread. For most road riders, these are the most useful all-rounders.
Fog lights are a separate category. They have a wide, flat beam with a sharp cut-off at the top, designed to sit low and light the road surface without bouncing off fog back into your eyes.
Size and power
Motorcycle auxiliary lights range from tiny pods of 2 inches or so up to larger round lights of 4.5 inches and more. Bigger usually means more light, but also more weight on the bars or crash bars and more current drawn from the bike.
Wattage figures on LED lights can be misleading, because some quote the theoretical maximum of the LEDs rather than what the light actually produces. If the lumen output is listed, it's a better guide to brightness.
Many lights now come with a built-in daytime running light, often in white or amber. That's handy for being seen during the day without blinding anyone.
Where to mount them
The most popular places are crash bars, fork legs and the lower edge of the fairing.
Crash bar mounts are sturdy and keep the lights low and wide, which looks good and spreads the light well. They're a common choice on adventure and touring bikes.
Fork mounts move with the steering, so the light always points where you're going. Make sure the clamps are the right diameter and that the lights and cables don't foul anything at full lock.
Fairing or bracket mounts suit bikes without crash bars, but check the bracket is strong enough. A light vibrating on a flimsy bracket will drift out of alignment quickly.
Wherever they go, mount the lights symmetrically and as low as practical, and keep the cables clear of hot exhausts, sharp edges and moving parts.
Wiring them up safely
This is the part that's easy to get wrong. A good installation has four parts.
A relay. Auxiliary lights draw enough current that running them straight through a handlebar switch can overload it. A relay lets a small switch turn the lights on while the main current goes through a separate, heavier circuit.
A fuse. Fit an inline fuse as close to the battery as possible, rated to suit the lights. If a wire ever chafes through, the fuse blows instead of the wiring melting.
A switch. Usually mounted on the handlebar, so you can turn the lights on and off without taking your hand off the grip.
A switched power feed. Take the trigger for the relay from an ignition-switched supply, so the lights can't be left on with the bike off and flatten the battery.
Many light kits include a ready-made wiring harness with the relay, fuse and switch built in. That's the easiest way to do a neat, safe job.
Before you fit anything, think about how much spare power your bike has. Smaller bikes in particular don't have a lot of spare charging capacity. LED lights draw much less than older halogen units, which is a big part of why they're so popular, but adding heated grips, a phone charger and a pair of lights can still add up.
The rules
We're not lawyers, and the rules can change, so please check the current UK lighting regulations before fitting extra lights to a road bike. That said, a few general points apply.
Extra lights that act as main beam should only be used when you'd normally use your main beam, and should switch off or be turned off when you dip for oncoming traffic. Wiring them so they go off with the dip switch makes this automatic.
Fog lights should only be used when visibility is seriously reduced, and turned off when it improves.
Lights must be properly aimed. A spotlight pointing too high will dazzle oncoming drivers even if it's wired correctly.
Some lights are sold for off-road use only. Read the product description before buying if you're fitting them to a road bike.
Aiming them
Park the bike on level ground facing a wall a few metres away, with the bike upright and loaded as you normally ride. The brightest part of each beam should sit just below the height of the light's centre. Driving lights can be aimed a little higher and straight ahead, while fog lights should sit low and level. Lock the brackets tight once you're happy, and check them again after your first ride.
You can browse our motorcycle lighting and motorcycle electrics ranges, including LED driving lights with daytime running lights and wiring harnesses, fog lights and mounting brackets.
This article is a general guide only. If you're not comfortable working on your bike's electrics, ask a qualified motorcycle technician to fit your lights.