– Confused by the pros and cons of derailleurs, hub gears and continuously variable transmission? We demystify this subject in our latest blog post. –
A lot of e-bike publicity focuses on the performance capabilities of the motor or the size of the battery. One often-overlooked area is gearing. Surely you just get the same choice as on a regular bike? Only to a point; the e-bike revolution has meant many things for e-bike design, one of which is an expansion of the gearing options available. With extra motor power available bigger and better performing gears can be used, gears which would be too heavy or difficult to pedal for most riders of non-electric bikes. These are covered in the Advanced Systems section later in the article.
The Basics: Derailleur and Hub Gears
The majority of e-bikes are equipped with derailleur gears, with hub gears being the major alternative choice. Both options go back many, many decades so the technology on both is well advanced and should work well for its intended purposes. But what are they and what are the pros and cons of each system?
Derailleur Gears

Derailleur gear set ups are so named as they always consist of a derailleur (or rear mech) in black here and a rear cassette (or rear cogs) which is the array of silver coloured sprockets. Some bikes use a front derailleur too (see infographic below) but front derailleurs are very rare on e-bikes.
Derailleur gears are external, with a rear derailleur usually connected to a cable. Tensioning the cable via a shifter on the handlebars means the derailleur guides the chain up over the sprockets onto the larger, easier to pedal ones (lower gears) ideal for hillclimbing. Letting the tension off in the cable means the spring in the derailleur pulls the chain downwards and outwards onto the smaller, harder to pedal gear sprockets (higher gears) for traveling at speed.
[Read more…] about Understanding Gearing on Ebikes