In 2019 we will be selling electric bikes from Ridgeback as well as providing conversion kits from Swytch and Panda. There are a number of different kinds of Electric bike and they all have advantages and disadvantages so it is worth understanding the different types so that an informed choice can be made.
Front Wheel Motor
A bike with a front wheel motor is usually coupled with a crank sensor so that when the cranks are turned the motor is engaged. When the battery is in the rear the weight distribution is even and the handling is improved. There is no gearing linked to the motor with this arrangement so there is no benefit of using the gearing through the motor to increase the range however, the advantage of this arrangement is that the chain is preserved. The Raleigh Array Low Step (right) is a great example of the front wheel design and has a great 7 speed nexus hub gear. The front motor wheel can be quickly released to fix punctures etc. This configuration has the advantage that it can be turned into an ordinary bike.
Rear drive electric bikes have the motor in the rear hub which also accommodates the gearing. This allows both the rider and the motor to drive the rear wheel which again preserves the chain from excessive stretch. If the battery is located in the rear then all the weight would be towards the rear which can affect handling and fixing rear wheel punctures can be onerous if there are not suitable connectors that allow the wheel to be released. The Forme Cromford 2 ELS (right) is a good example of rear drive and accommodates rear wheel removal to fix punctures brilliantly. With all the weight in the back the bike does have the advantage of greater traction in poor conditions. This bike is a low step through frame and has the advantage of being turned into an ordinary bike.
Crank Drive integrate the motor with the cranks to drive the rear wheel. the main advantage of this is that the power is coupled with the gearing which results in an increase in range. This is seen as the best arrangement as it puts the weight in the centre of the bike which can improve handling and there is the benefit of the gears being powered by the motor. This disadvantage is the excessive ware on the chain as both the rider and the motor is driving the chain which results in stretching. There are special hardened chains that can be used in this circumstance and this is especially useful if driving a 10 speed derailleur system. The Ridgeback Electron Plus is a good example of this arrangement which uses the Shimano STEPS system.
The Swytch units are designed to convert your bike to an E-Bike with a front wheel drive. The battery and control unit is located in a handy bar bag and the conversion can take less than an hour. All the weight is on the front which can affect handling however the system design minimises the weight. There are many options available to accommodate different types of bikes and different battery capacities. It can be applied to almost any bike and potentially the motor can be built into a colour coordinated rim.