Bosch ebike mid drive systems explained

Bosch Mid Drive System for Electric Bikes

The BOSCH electric bike system has taken the European electric bike market by storm. It is now used by over 50 electric bike manufacturers around the world.

This German designed electric bike system is relatively new to Australian shores, with the first models being made available early 2013. Gazelle (Netherlands), Gepida (Hungary) and Haibike (Germany) electric bike manufacturers were among the first to bring this state of the art technology to the Australian e-bike enthusiasts.

Often referred to as Generation 1 or the “Classic” line drive system this system is renowned for fantastic performance, great range and excellent hill climbing ability.

Not one to rest on their laurels BOSCH launched the Generation 2 mid drive electric bike drive systems in 2013.

The Lineup - Technical Specifications

The lineup now includes 3 mid-drive electric bike drive systems with the key specification shown in the table below

Motor System Classic+ Line Active Line Performance Line
Power 250 Watt 250 Watt 250 Watt
Torque 50 Nm 48 Nm 60 Nm
Maximum Assist 250% 225% 275%
Shift Detection No Yes Yes

So now for the million dollar question...

Which Bosch electric bike system is right for me?

The good news is that part of the decision will be influenced by what you’re planning to use your electric bike for. The BOSCH Classic+ Line is featured predominantly on electric bikes that will spend most of their life on the road and cycle paths. With its proven reliability and high torque output it is the perfect partner for hard working commuter e-bikes the world over such as the Lombardo Amantea City.

For those of you who are planning venturing off road this is generally where the Active Line and Performance Line systems are used. (Although the Active line is also used on some very nice city style ebikes such as the Gazelle range).

Both the Active Line and Performance Line BOSCH drive systems use a smaller front sprocket to drive the chain (via the crank). The main reasons for this design change is to increase ground clearance and reduce “chain slap” (this is where the rear derailleur bounces around when the bike is being ridden over rough ground). Very handy when you’re riding up or down rocky terrain such as Mt Joyce, Mt Cootha and Bunya mountain bike trails in and around Brisbane.

The extra 12Nm of torque of the Performance Line is noticeable in its acceleration from a standing start, and depending on the gear ratios that the motor is mated to it will be the better climber over very steep terrain (15% and above). Great for mountain bikes.

BOSCH have done an amazing job when it comes to the overall design and packing of their mid drive electric bike systems. With all of the technology on offer it can be easy to forget the other factors that have a huge impact on the way a bike handles and performance.

Frame design, gear choice, wheel size, tyre choice and bike set up all play their part in how your new e-bike will perform. Ultimately the best way to decide is by testing riding a number of bikes and then deciding for yourself which bike and drive system is right for you.