Which Bosch Motor for your E-bike?

Bosch powers an enormous number of the bikes we sell at Electric Bikes Guildford, and features across the whole spectrum of types, from monstrously powerful mountain bikes to lightly built urban city bikes. This article aims to explain the different Bosch motors available and also explains why we have come to so heavily trust a drive unit manufacturer you may have first seen on the front of your washing machine or power drill? Quite simply, their motors provide some of the most powerful, reliable, and responsive assistance available.  

Bosch currently have five motors available, which can be confusing if you’re looking for the right bike for the job. Bosch have customized each of their motors to be the most efficient and cost effective for the specialty of the bikes they are used for – you won’t want a lightly built city motor pulling you up a mountain, nor the extra weight and expense of a mountain bike motor if you only want to take your bike on roads. Other motors are built for more general use – functioning equally well on trails and on urban commutes. In order to help find the motor you’re looking for, we’ve put together a quick guide on each of Bosch’s available motors, and of course we’re always happy to talk in store about any questions you might have. 

New ActiveLine

The lightest of Bosch’s motors weighing in at only 2.9kg, the ActiveLine 3.0 is a sleek motor packing its power into a tightly wrapped, compact package. Bikes with ActiveLine motors is noticeably more compact than the other motors in the range and can even make it difficult to tell apart from their non-electric counterparts, as the motor snugly fits in among the pedals and does very little to distort the silhouette of the bike.Bosch Active Line Motor

Unlike previous motors produced by Bosch the motors has a normal sized chain ring and there is no internal gearing in the motor. This means there is no resistance and noise is effectively reduced too, so the quiet of a relaxed ride isn’t disturbed by the sounds of the motor. The maximum torque available from the ActiveLine motor is 40Nm, which is not to be sniffed at; while we would recommend a more powerful motor for tough mountain routes, there is more than enough assistance available here to power you over off-road trails, and benefits from the light build of the motor, providing that the other components of the bike are built accordingly. The maximum drive assistance available in Turbo mode is 250%, a significant boost to your speed that is nonetheless controllable and relaxing, and ideal for city rides. As the lightest and least powerful of the motors, the ActiveLine is a smart choice for urban cyclists who want to budget their choice of e bike according to what they want out of their bike, and not pay more for features they don’t need. The ActiveLine and ActiveLine Plus are winners of the Red Dot Design Award 2017, a prestigious seal of quality. 

New ActiveLine Plus 

The slightly heavier, more versatile cousin of the ActiveLine, the ActiveLine Plus weighs in at 3.2kg so is still astonishingly light despite the boost in speed and power.  The ActiveLine Plus maintains many of the benefits of the ActiveLine with noise reduction, no resistance, a small, sleek build, and harmonious acceleration all still noticeable advantages. However, the ActiveLine Plus improves on Torque strength with 50Nm, and assistance drive available with 270%, making it easier to break out of the city limits and power over off-road trails. If your ride is quite hilly and you are looking for a bit more help then we would recommend this over the plain ActiveLine. It is one of the newest motors in Bosch’s range, and therefore we expect to see it on more models in future. 


The PerformanceLine is Bosch’s first motor designed specifically for off road. It is the previous version to the PerformanceLine CX (see below) but is still used on a number of bikes – especially hybrid / cross bikes where the extra power is welcome. It weighs in at 4.0kg and is capable of 63 NM of torque. Despite an increase in size and weight, the motor doesn’t suffer from bulk, maintaining the sleek elegance of its lighter counterparts, and making it perfectly suitable for city trips.Bosch Perfomanceline motor In turbos the assistance level rises to 275% meaning that it is capable of even higher speeds and power to for sudden, sporty acceleration to lift you easily over steep inclines. Many models of the PerformanceLine motor also offer eShift solutions from Nuvinci, Rhollo and Shimano, allowing for easy, electronic gear shifting. The safe chain run keeps the chain on track, preventing derailment and incorrect loading. Overall this means that the PerformanceLine is a sportier option than the ActiveLine, without stepping into the high end production of the PerformanceLine CX.  

PerformanceLine Speed variant 

 The PerformanceLine Speed variant is for ‘speed pedelecs’ capable of an assisted speed of up to 45 km/h or about 30 mph. Speed pedelecs are not legal in this country without a special license and clearance from the DVLA. We can help you through this process on request,

PerformanceLine CX 

The unapologetic monster of the Bosch line, the PerformanceLine CX is found almost mainly on mountain bikes either  full suspension or hardtail models or other performance bikes – such as our most popular bike the KTM Macina Cross 9.  Despite a significantly its additional oomph it weighs no more than its predecessor – the PerformanceLine at under 4 kg.   The CX provides a whopping maximum of 75Nm of torque power to carry you up even the harshest inclines. This level of power means that less focus needs to be spent on changing gear, as the power available from the motor alone means that momentum is easier to carry between shifts of downhill to uphill.  The available assistance of 300% means it packs the biggest punch in acceleration. This is kept directly at your beck and call thanks to Direct Flow, which makes the assistance available as soon as you step on the pedals. Bosch PerformanceLine CX MotorThe new models of the CX features eMTB mode, a highly useful feature which changes the assistance level without your input. The eMTB mode dramatically improves the performance of the drive unit on off road terrain, creating a more powerful startup for greater support when starting on uneven ground. The outer body of the motor is built to withstand impact from loose rocks as you leave the city behind. The philosophy behind the design of the PerformanceLine CX is straightforward – to keep all of your focus on your performance, and not on your bike. By providing enough power to drive you up any hill, from any starting position, and with the strength and durability to maintain its breathtaking drive, you can put all your effort into enjoying and mastering your experience as a mountain biker.