A hub dynamo is a generator integrated into the front wheel that produces electrical energy while riding. This energy is primarily used to power the bicycle lights . Unlike traditional side-mounted dynamos, the hub dynamo operates almost silently, is weather-independent, and is particularly efficient.

The hub dynamo is a power generation system integrated into the wheel hub. The rotation of the front wheel moves a magnetic field inside, which generates an electrical voltage. The energy is then transmitted via cables to the front and rear lights.

How it works

Inside a hub dynamo are permanent magnets and coils. When riding, the magnet ring rotates with the wheel and induces alternating current in the coils. This current is used directly for the bicycle lights or – in modern systems – temporarily stored (e.g., in standlight capacitors).

Typical performance data:

• Voltage: 6 volts

• Power: 3 watts (according to German road traffic regulations)

Areas of application

Hub dynamos are primarily used in:

• City and trekking bikes

• Everyday and commuter bicycles

• Touring bikes

• Children's and youth bicycles

• cargo bikes

They are also becoming increasingly common on sporty bicycles, especially on models that focus on everyday usability.

Advantages of a hub dynamo

• Low maintenance: No friction roller, minimal wear.

• Weatherproof: Works reliably in wet, snowy and dirty conditions

• High efficiency: Low additional rolling resistance

• Convenience: Light always available, no more forgetting to turn it on.

• Quiet: Virtually noiseless operation

Disadvantages of a hub dynamo

• Higher weight: Compared to battery-powered lights

• Retrofitting is complex: replacing the front wheel or re-spoked the wheel is necessary.

• Cost: High-quality hub dynamos are more expensive than simple side-running dynamos.

Hub dynamo vs. sidewall dynamo

In Germany, hub dynamos are approved according to the German Road Traffic Regulations (StVZO) and meet the legal requirements for bicycle lighting. In combination with approved lights, they are permitted for unrestricted use on public roads.

Modern developments

Current hub dynamos offer:

• Parking light functions

• USB charging options (via add-on modules)

• Very low rolling resistance , barely noticeable while driving.

A hub dynamo stands for comfort, safety, and everyday usability . It is a particularly reliable solution for frequent riders, commuters, and touring cyclists, ensuring consistently functioning lighting.