Lights are legally required on e-bikes when ridden in hours of darkness on UK roads — and practically useful at any time of low visibility. The right setup for an e-bike differs from a standard bicycle because the speed profile is different. This guide covers what the law requires, what the market offers, and what we recommend for different uses.
UK Legal Requirements
The Road Vehicles Lighting Regulations 1989 (as amended) require cycle lights when riding between sunset and sunrise on public roads. The legal minimum:
- Front: one white light (or steady-burning)
- Rear: one red light (can be flashing — flashing is legal since 2005)
- Rear reflector: red, BS EN 13032-1 compliant (usually included with the bike)
- Pedal reflectors: amber (usually included with the bike)
There is no minimum lumen requirement in UK law — only that the light is visible. However, riding at e-bike speed (up to 15.5 mph assistance, often faster on descents) in low light with a 10-lumen light is dangerous regardless of legality. We recommend a minimum of 200 lumens front and 50 lumens rear for UK road riding.
Integrated vs Independent Lights
Battery-Powered from E-Bike Battery
Many higher-end commuter e-bikes include lights powered from the main battery — front and rear, always active when the bike is on. These are ideal: they cannot be forgotten, cannot run flat independently, and are typically brighter than USB-rechargeable lights at the same price point. If your e-bike includes integrated lights, use them. Check: do they stay on when the motor system is in standby, or only when the motor is active?
USB-Rechargeable Independent Lights
The standard choice for e-bikes without integrated lighting. Rechargeable from USB (increasingly USB-C), easily transferred between bikes, no batteries to replace. Runtime varies widely — a 500-lumen light at full power might run 2-3 hours; on eco mode (200 lumens), 8-12 hours. For daily commuting under 1 hour each way, USB lights are practical. For longer use, carry a spare battery bank or use a dynamo system.
Lumen Guide by Use Case
| Use | Front lumens | Rear lumens | Recommended lights |
|---|---|---|---|
| Urban commuting, lit streets | 200-400 lm | 50-100 lm | Cateye AMPP300, Exposure TraceR |
| Suburban/unlit roads | 400-800 lm | 75-150 lm | Lezyne Mega Drive, Knog PWR Road |
| Rural unlit roads | 800-1600 lm | 100-200 lm | Exposure Strada MK10, Magicshine ALLTY 1000 |
| Off-road trail riding | 1000-2500 lm | Not required | Magicshine MONTEER 6500, Exposure Six Pack |
Mounting Options
Standard GoPro-type mounts work with most action cameras. For lights: handlebar mounts (most common — 22mm and 31.8mm clamp sizes), stem mounts (keeps handlebars clear), fork crown mounts (specific to some light/bike combinations), and helmet mounts (useful for trail riding where you want the light to point where you look). On e-bikes with wide handlebars (common on e-MTBs): ensure your light mount clamps to the correct diameter section — the central grip area is usually 22.2mm but varies.
Dynamo Lighting: The Long-Distance Option
Hub dynamos (SON, Shutter Precision) provide unlimited lighting power from wheel rotation — no battery, no recharging, always on. They are the right choice for touring, long commutes, and any situation where independent light batteries are a logistical burden. However: they require a dynamo hub, specific wheel build, and dynamo-specific light connections. Best specified when building a new wheel rather than retrofitted. Not relevant for e-MTBs, off-road bikes, or short commuters.