Words by Eddie

on 20/09/2019 11:18:00

What Everyone Asks

1. What is the range of an electric bike?

The range of a fully charged battery varies dramatically. It is usually between 5 to 60 miles with gentle pedaling depending on the many variables. There has been a trend for manufacturers to over estimate the range of their products. The Voltage times Capacity (measured in Watt Hours) gives an indication of the range. Aside from battery capacity factors effecting range include:

Bike, rider and luggage weight

Hills, terrain and tyres

Tyre pressure makes a huge difference

Suspension and rolling resistance caused by components

rider input and gearing used

motor/controller power rating

Motors with a higher nominal power rating may offer more hill climbing ability (torque) but will reduce the range.

Most of the power is drained when moving off and on hills so pedaling at these points will preserve the power.

If you have specific requirements it is best to talk to us and get some advice before spending your hard earned cash.

2. How fast will an electric bicycle go?

To gain exemption from road tax, road insurance, MOT tests, vehicle registration, the requirement of a driving licence and wearing a motorcycle helmet the speed under power is restricted to 15.5 miles per hour. They can of course be cycled beyond this speed.

To go faster requires more power, so a more powerful motor is required to go faster. And motors are “wound” or designed to operate at a specific speed. For example, a motor that is intended for a 20” wheel must turn much faster than a motor intended for a 26” wheel to achieve the 15 mph UK limit.

Because of this, just being powerful is not enough to gain higher speed. It is possible to have a powerful motor that will not turn any faster - limiting speed.

A 180 watt motor intended for a 50 kg office lady in Shanghai who cannot go faster (by law) than 12 mph is not going to help a 90 kg European go 15 MPH. Most electric bike motors are, in fact, designed for places where people are smaller and bikes are limited in speed.

Like people – as batteries age, their performance decreases. (Actually, in the first 25 or so charge / discharge cycles, many batteries get better, and then start a gradual decline).

If the battery has been poorly treated – such as heavy use (deep discharge cycles, non pedal assisted starts), the wrong charger, stored in a hot damp place, exposed to excessive cold, then the performance will suffer.

3. Do I need to pedal and electric bike?

Strictly speaking when on the road the law requires you to pedal with the power assisting your pedaling (PAS), however on some models you have a throttle which can be used without pedaling or in conjunction with the pedals.

Hills slow you down so you need to pedal to maintain speed, although bikes designed for hill climbing are better at maintaining speed on hills.

4. What are the running costs of an electric bicycle?

Other than charging the batteries at a cost of approximately 7 pence per full charge there are no other significant running costs. You should carry out basic maintenance as you would with a normal pedal cycle, however the electronic parts of the bikes are designed to be trouble and maintenance free.

5. How can I tell a good electric bike from a bad electric bike?

Clicking here will take you to our buying guide!

6. Does the battery recharge when I pedal my electric bicycle?

We are asked this question by many customers. The answer that applies to most electric bicycles is no but you do preserve the battery power by pedalling! There are a few exceptions using re-gen for braking but this technology adds weight, more expensive components, and the benefit is pretty negligible considering bike stopping distances and the power lost in the system.

Re-gen is slang for “Regenerative”. Some motors (direct drive) can generate electricity when the rider propels the bike by pedalling, or while when going down hill or braking.

A motor and a generator are actually the same thing. If you turn a motor shaft, you will generate electricity. If you energized a generator you would get a motor.

So on an electric bike that does not have a planetary transmission, or a free-wheel between the motor and the hub, and has a controller that will allow the motor to become a generator – you can have re-gen.

Re-gen, however, is not as useful as it sounds. To recharge the bike while riding requires you to ride a long way against the resistance of the motor. You must create more work (due to efficiency losses) to recharge the battery than the work that the energy in the battery can do through the motor. (Awkward to explain.) Basically, you have to work harder to charge the battery enough to propel the bike 10 miles than it would have taken you to ride 10 miles by yourself. Also charging lithium batteries is complicated and regen motors in use tend not to generate a stable enough supply of power.

If you have long descents regen may work well but rarely enough to warrant the extra cost and complexity.

7. Are there any UK laws I need to be aware of?

The UK law differs slightly from the EU law and hence there is some confusion but if you adhere to the following you should be acting within our current regulatory guidelines.

· average continuous motor power output no more than 200 watts

· maximum speed under power 15 mph.

· must have functioning pedals.

· the use of a throttle is currently allowed.

· weight must not be more than 40 kg unless a tandem or tricycle.

· riders age must be at least 14 years of age. (sorry kids, your time will come)

*NB* Laws can and do change without prior warning. These are accurate at the time of writing and we shall endeavour to keep them up-to-date.

We were the only UK e-Bike retailer invited to the DfT review of the EAPC regulations. Our goals were to:

  • Remove the weight limit
  • Ensure the throttle remains an option for UK e-cyclists
  • Get the UK to adopt the L1e category allowing speed pedelecs.
  • Manufacturers on the committee generally wanted to see a complete harmonisation with EU laws and adoption of the EN15194 standard.
  • The laws should be changing in 2016 and you will have to wait and see what was agreed.

For those of you with a real thirst for information and a bit of time on your hands follow the link below to the draft European Standard likely to pass into law shortly

To see our electric bike special offers click here.