Riding at night: headlight, visibility and fatigue

Do the sum once and it will stay with you. At 90 km/h you cover 25 metres every second. Between the moment an obstacle enters your beam and the moment the bike is stopped, you need roughly one second of perception and reaction plus around forty metres of braking on a dry road: about 70 metres in total. A dipped beam in good order usefully lights 30 to 40 of them. Put another way, as soon as you go past 60 or 70 km/h on dipped beam, you are riding faster than you can see.

That doesn't mean crawling around all night. It means the margin has to be found elsewhere: in the beam aim, in a clean lens and a clean visor, in the way you absorb oncoming headlights, and in your own fatigue. A bike that lights the road badly at night is nearly always a question of adjustment and upkeep, not a shortage of watts.

Your useful range is shorter than your stopping distance

The figures below are orders of magnitude on a dry road, with firm braking and a decent tyre. In the wet, stretch the "stopping distance" column by about 40 %.

Two lessons. Main beam is not a comfort feature: it is the only setting where your vision covers your stopping distance beyond 80 km/h. On an empty road you use it by default and drop to dipped when someone appears, not the other way round. And on dipped beam, the real safe speed on an unfamiliar road is somewhere around 70 km/h.

LED or halogen: what actually changes

The most stubborn myth is that a more powerful bulb lights further. It sticks because packaging shouts about lumens, and a big number is reassuring. But range depends first on the optic: it is the reflector or the lens that decides where the light goes.

• Output doesn't make range. A standard H4 halogen bulb produces something like 1,000 to 1,500 lumens on dipped beam. An LED module claiming 3,000 lumens, dropped into an optic designed for a filament, can light less far, because the hot spot is smeared.
• The position of the light source is the real criterion. A filament is a small volume in a precise place; an LED chip is a flat surface. If the kit maker hasn't reproduced the geometry of the filament, the beam goes fuzzy at the top and hollow in the middle.
• Colour temperature changes comfort, not distance. Halogen sits around 3,200 K, LED between 5,000 and 6,500 K. Cool white gives better contrast on dry tarmac; in fog and heavy rain it scatters more and tires you faster.
• Current draw matters on older machines. A halogen dipped beam pulls 55 W, an equivalent LED module 15 to 25 W. On a bike with a marginal alternator, those 30 W back in the budget count as soon as you add heated grips.
• Approval isn't optional. Lighting approval in the UK runs on the ECE system, the same one recognised across the EU, and the approval mark is moulded into the lens. Fitting an LED bulb into a headlamp approved for a filament source is not a compliant swap. Check the marking on your unit and the current rules before you buy, not after.

On budget: reckon on £10 to £20 for a good branded halogen bulb, £25 to £70 for a serious LED module, and £130 to £500 for a complete approved LED headlamp, whether original part or aftermarket.

Setting the beam, and setting it loaded

This is the free job that changes the most, and almost nobody does it. A beam set with the bike unladen and on its stand will be pointing at the tarmac fifteen metres ahead the moment you load a top box and a pillion. The other way round, a headlamp that has crept downwards leaves you in the dark at forty metres. The method, on level ground, facing a wall:

• Load the bike the way you ride it. If you're going two-up with luggage, put the pillion and the luggage on board: the setting only means anything in the real configuration.
• Stand 5 or 10 metres from the wall, front wheel square to it, bike upright on both wheels rather than on the side stand.
• Mark the height of the centre of the headlamp on the wall with tape, along with the centreline of the bike.
• Switch on the dipped beam and look at the cut-off, that crisp horizontal line above which there is almost no light left. It should fall below your height mark, not above it. On a unit built for left-hand traffic the cut-off kicks up towards the nearside, the left; a lamp still set for right-hand traffic — a continental import, typically — throws that kick-up straight into the eyes of traffic coming the other way.
• The drop is of the order of 1 to 2 % of the distance, so 5 to 10 cm at 5 metres, 10 to 20 cm at 10 metres. The exact value is in the owner's manual: it depends on headlamp height.

The MOT — annual once the bike is three years old — includes a headlamp aim check, but it's carried out with the machine unladen: a pass tells you nothing about how the beam sits with a pillion and a full top box.

If the bike squats heavily two-up, the problem isn't the headlamp but the rear preload. Sort the attitude first, set the lamp afterwards — never the reverse. The method is set out in the guide to suspension preload adjustment.

Auxiliary lights: useful, but mounted and wired properly

A well-placed pair of auxiliary lights does more than any bulb change. Badly placed, they dazzle you off wet tarmac and turn the road into a blur.

• Low and wide for relief. Mounted at the level of the lower fairings or the crash bars, they graze the surface and bring out holes, gravel and edges. That is exactly what a standard headlamp misses.
• High for range, but with discipline. Up at the fork yoke, they reach a long way and dazzle everyone. They only make sense if you can kill them instantly with your thumb.
• Wire them through a relay and a dedicated fuse. Never spliced straight into the original dipped-beam wire: neither the loom nor the switchgear is sized for it.
• Check your electrical budget. Two serious LED auxiliaries draw 20 to 60 W between them. No issue on a recent machine; on an older one already loaded, add it up before you add anything.

Reckon on £70 to £130 for a decent pair, £170 to £350 for an approved branded pair with brackets and a dedicated loom.

Visor, misting and reflections

At night your helmet is an optical filter. It decides a good part of what you see.

• Clear visor, no exceptions. A tinted visor cuts 15 to 50 % of the light depending on its category. What feels comfortable at sunset becomes dangerous forty minutes later. Photochromics often take 30 seconds to a minute to clear, which is a long time at the mouth of a tunnel.
• A scratched visor scatters. Micro-scratches invisible in daylight turn every oncoming headlight into a starburst. If you ride at night often, a new visor every two years pays for itself on its own, at £25 to £50.
• Misting is beaten by ventilation, not by a cloth. A double-glazed anti-fog insert is still the most reliable answer, around £18 to £35. Close your collar so exhaled air doesn't rise, and leave the chin vent open even in cold weather.
• Clean the headlamp lens. A lens coated in flies and road film can lose 20 to 30 % of its output. Two minutes before you set off.

The rest of the kit matters too: choosing a helmet and its visor is covered in the guide to helmet types and sizing.

Taking dazzle without losing the road

When a vehicle comes the other way, your pupil closes in a fraction of a second. Once it has passed, it takes several seconds to reopen — and during that gap you see less well than you did before the pass, at exactly the moment you get the full width of the road back.

The counter is three habits. Slow down before the pass rather than during it: you'll have the margin at the point where your vision is degraded. Shift your gaze towards the nearside edge of the road and follow the line without staring at the headlights, which preserves part of your dark adaptation. And don't answer with a flash when the other driver has forgotten to dip: you dazzle them in turn, and now you're both blind in the same place.

Night fatigue is prepared for, not fought

Riding at night costs more attention than riding in daylight, for two reasons that stack up. The brain works harder to read a scene short on contrast, and the body clock digs a genuine hole in alertness between 2 and 5 in the morning, whatever number of hours you slept.

• Shorten your break intervals. If you stop every two hours in daylight, move to 1 hr 15 or 1 hr 30 at night. Ten minutes on your feet beats three minutes sat on the bike.
• Count the cold into the equation. Between 8 pm and 3 am the temperature frequently drops 5 to 10 °C, and wind chill at 110 km/h does the rest. Cold eats alertness before it starts to hurt.
• Eat light and don't count on caffeine to see you through a second night: it masks drowsiness without removing it, and the effect falls away all at once.
• Yawning and no memory of the last few miles are stop signals, not inconveniences to push through.

Add a greasy road surface to the darkness and distances stretch further still: the reflexes to adapt are set out in the article on riding in the rain.

The five-minute departure routine

Before a night ride, in this order: wipe the headlamp lens and the rear reflector; check dipped beam, main beam, indicators and brake light, including the one triggered by the rear brake, which is usually the first to fail; run a microfibre over the visor, outside then inside; check tyre pressures; and if you're setting off loaded, glance at the beam against a wall before you leave the neighbourhood.

The values that depend on your machine — headlamp aim height, tyre pressures solo and two-up, maximum load the lighting circuit will take — are in the manufacturer's documentation. L'Atelier's technical assistant finds them from the make, model and year, and tells you which circuit to hang an auxiliary light on without overloading the original loom.