How e-bikes work (non technical explanation)
How e-bikes work (non technical explanation)
How e-bikes work: "A hybrid vehicle using human and electrical energy"
Bicycles are a brilliant invention, they are probably the most efficient transport ever invented, and adding sustainable auxiliary electric power to a bicycle is a great innovation.
This article does not apply to electric motorbikes or electric mopeds. This article applies to Electrically Assisted Pedal Cycles (EAPC).
An EAPC is propelled using both Human and Electrical energy, the energy supplied by the human is supplemented by the electric motor.
In the face of jargon and sales speil from a shop Exp​ert just try to remember an e-bike is just a bike with a motor, it is not a rocket ship. It's performance is limited by laws of physics and laws of the country in which you ride it.
Motor size limit.
In the UK your motor size is limited to 250Watts. This will limit how fast you can accelerate and what top speed you can reach. but just in case there is an Albert Einstein or Nicola Tesla out there who can get their e-bike motor to over perform then UK law will limit your speed to 25 km/hour.
you may ask if 250W is enough? then 250W is coincidently about the same power a top sprinter pushes out when competing, so having a 250W motor is like having the assistance of a serious athlete moving you. for the majority of people this is enough.
There are some very good resons for limitting ebikes to 25 km/hr. It is very costly to investigate deaths caused in a traffic accident, also it costs the NHS health service a fortune reassembling people. This excludes the physical and mental pain associated with accidents.
It is possible to strap a very big motor onto any old bike frame (see youtube for examples) and make a stupidly fast e-bike. If you want the thrill of doing this then restrict yourself to private land to avoid coming into contact with innocent road users. Speed is thrilling, but please think about your impacts on others or the back of a bus.
In my view a dead e-bike rider is no good to me as they cant buy any of my e-bikes. Please be safe and buy my e-bikes..
Electric Motor Location on e-bike
There are lot of articles comparing Mid-drive motors and Wheel hub motors as if it is going to make hub motors obsolete. However that’s not true. M-eV offers both Mid-drive as both have pros and cons. it is not about fitting the newest priciest technology to your e-bike it is about selecting the right equipment for your need.
Front Hub Motors
Front hub motors are the cheapest and easiest to maintain. they are also well suited to riding on paved roads despite what some sellers will tell you as they promote pricier options. Front hub motors give the rider a sensation of being pulled along which some shops say is not as nice as being pushed. At normal speeds in average road conditions how many of us can really tell the difference between front and rear wheel drive in a car? Arguments for both options exist usually citing extreme condition performance. Also I suggest you try not to get bogged down by centre of gravity arguments. for sure e-bike components affect the centre of gravity and possibly handling but no more than putting on or losing a bit of body weight, or where you place your shopping. Technically, weight distribution on an ebike does affect how it rides but much less than what some people will tell you. How a bike rides is more affected by how you ride it and what you try to do with it.
A front hub motor may cause wheel spin on loose surfaces if too much power is applied, also there may be a problem on landing during freestyle stunt riding. if you are going to ride your e-bike on reasonable roads at sensible speeds and can control your urge to perform bunny hops and wheelies then maybe you could test out a front hub drive e-bike to see if it is suitable for you.
Rear Hub Motors
In terms of price this is the next level up, and seems to be the most prevalent drive option in the market.
Again the laws of physics and the country apply with supporters of both front and rear wheel drive propulsion making their opinions known.
A rear wheel hub drive will push you along. wheel spin is possible on loose road surfaces if that is what you want. But most riders are not trying to Drag Race their e-bikes so wheel spin is not going to be a problem.
The key to making your choice is how do you feel when riding your e-bike. Does it feel comfortable and responsive?
Can you be swayed by the sales person to buy the most expensive technology?
Do you need 21 gears on your e-bike. consider that the bike wheel is being rotated by the hub motor and that the expensive gear set is being by-passed.
Mid Drive Motors.
These are different to hub motors in that they turn the crank on the bike just like pedalling. This means the gears on the bike can be used to optimise how much torque is applied to the rear wheel.
This benefit comes at a price as mid drive motors represent about 50% of the price of the bike.
As with hub motors the motor size is limited to 250Watts and upon reaching 25km / hour the electricity to the motor is cut off.
Mid drive motors are touted as giving the rider a similar experience to that of riding a traditional bike with assistance. It is often aimed at cyclists who go off road, up and down mountain trails and who really do benefit from having gears.
Friction Drive.
These are offered as a quick addon to transform any bike to an ebike. The drive is provided by a small motor held against the tyre. This relys on the friction between the drive motor and tyre, if friction reduces as in wet conditions these units fail.
Generally these are not a serious contributer to the e-bike market.
Talk to us about you want your e-bike for and we will try to match you up with an e-bike that meets your needs. we can also do specials as we have a close relationship with several manufacturers.