JARGON BUSTER (CONT’D)

seat tube. This lowers the bike's centre of gravity, to improve handling and performance.

OVERRUN

Motor assistance usually continues for a short period after the rider stops pedalling. This is called overrun and can be useful on technical climbs where you need to change your pedal-stroke timing to avoid ground strikes.

PEAK POWER

UK law limits e-bike motors to 250W of continuous, standard power. Many manufacturers claim peak power higher than this, but this output is only in certain circumstances and for short periods. If a motor doesn’t deliver as much power as expected, it may be because it’s reached a 250W continuous peak and is ‘throttling back’ to avoid exceeding the limit.

PEDAL-ASSIST/PEDELEC (PEDAL ELECTRIC CYCLE)

Terms that describe e-bikes with motors that only provide assistance when the rider is pedalling. The only type of e-MTB that can be legally used on UK trails.

SUPPORT PERCENTAGE

How much the motor augments a rider’s pedalling inputs. A drive unit with 100 per cent support will essentially double the rider’s power – so if they put out 50w, the motor will also provide 50w, amounting to an overall system power of 100w. Support percentages are directly related to motor peak power, and usually in the region of 300 to 400 per cent.

TORQUE

The amount of twisting or rotational force the motor provides. A higher torque value, given in Newton metres (Nm), will make the motor feel more powerful.

WALK ASSIST

A feature most e-bikes have, where they’re able to propel themselves at low speed without the rider pedalling, making it easier to push them up steep sections. WATTS (W)

The measurement of motor power.

WATT HOURS (WH)

A standard measure of electricity, equivalent to the power consumption of one Watt for one hour. E-bike battery capacity varies from 320Wh to 900Wh, and as technology improves, so does energy density, where more power can be contained within the same space.