It is illegal to ride a bicycle on a motorway. Perhaps the rider stopped on the M25 at the weekend reasoned that their e-bike was too fast and powerful to be legally considered an electrically assisted pedal cycle (EAPC)… except that was why the police then confiscated it.

The BBC reports that police stopped the rider on the motorway hard shoulder at Potters Bar in Hertfordshire on Sunday.

In a post on Twitter, Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit said: “With a power output of over 250w and a maximum speed of 22mph it falls outside of EAPC regulations and cannot be ridden on our roads. Vehicle seized, rider reported.”

The bike in question looks to be a Samebike LO26-II, which comes with a 500W motor.

Founded in 2014, Samebike is based in Guangzhou City, China. After previously targeting the US and continental European markets, the brand does now have a UK warehouse and also a UK website on which the LO26-II is variously described as a ‘moped electric bike’, ‘electric bike’ and ‘moped electric bicycle’.

> When does an e-bike officially become a moped?

In UK law, an EAPC doesn’t need to be registered, it isn’t subject to vehicle excise duty and it doesn’t have to be insured as a motor vehicle.

There are three main requirements to qualify:

• The bike must be fitted with pedals that are capable of propelling it
• The maximum continuous rated power of the electric motor must not exceed 250W
• The electrical assistance must cut-off when the vehicle reaches 15.5mph

Pedal-assist electric vehicles with more powerful motors and a maximum assisted speed up to 28mph are often referred to as speed pedelecs. However, in the UK, there’s no specific legislation for speed pedelecs, so if you’re riding one, you’re legally riding a moped, which means all the laws regarding mopeds apply.

Such a vehicle will also need to be type approved as a motor vehicle. In the event you actually manage to achieve that, you’d then also need a driving licence, registration, tax, insurance and a motorbike helmet to ride the thing.

> Buying and riding an S-pedelec in the UK

Commenting on Sunday’s incident, Jamie Cooper, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: "I would like to remind everyone that it is illegal and unsafe to ride any type of pedal cycle on the motorway.

"Some pedal cycles – like the one stopped by our officers – are also illegal on any road in the United Kingdom, due to them falling outside of the EAPC regulations."