Bosch announce its new lightweight Performance Line SX e-bike motor

Bosch Performance Line SX lightweight motor
(Image credit: Bosch)

Bosch eBike has announced a brand new motor, the Performance Line SX. The new motor is aimed to cater to the burgeoning lightweight electric mountain bike market, as well as e-gravel and urban duties.

Loads of brands are currently releasing lightweight e-MTBs, attempting to offer a more playful and maneuverable ride feel that you get from a non-powered mountain bike, whilst still having the support of a motor on the climbs. Currently, the two main motor providers are Fazua and TQ which have been featured on bikes like Trek's EXe, BMC Fourstroke AMP LT, Scott Lumen, and Lapierre's recently released E-Zesty.

"Now that most types of bicycle have been electrified, the individual categories are becoming even more diverse. With the new Performance Line SX, we are primarily targeting sporty riders, for whom a low total weight is important for riding fast and experiencing a natural flow," explains Claus Fleischer, CEO of Bosch eBike Systems. "Our goal was to maintain the typical Bosch quality, riding performance, and reliability and transfer these to light, agile bikes. With the Performance Line SX, state-of-the-art eBike designs and maximum riding fun can be optimally combined."

The new Performance Line SX motor delivers up to 55Nm of torque and can deliver a continuous output of 250w with a peak output of up to 600w. Motor resistance has also been reduced by 50 percent compared to other Bosch drive units which should make it a lot easier to ride above the motor threshold. Bosch says the new motor weighs approximately 2kg (Performance Line SX drive unit only) and approximately 4kg for the complete system (Performance Line SX drive unit, CompactTube 400, Mini Remote, and System Controller). That's a claimed saving of around 900g on the motor unit alone over Bosch's current Performance Line CX motor, which is one of the best e-MTB motors available.

Bosch Performance Line SX lightweight motor being ridden off-road

Lightweight e-MTBs offer more agility but with the climbing assistance of a motor (Image credit: Bosch)

For comparison, the TQ HPR50 motor has a lower torque output of 50Nm but also undercuts the weight, hitting the scales at a claimed 1,850g for the motor. Fazua was one of the first brands to produce a lightweight e-MTB motor and their Ride 60 motor weighs 1,960g and has 60Nm of torque. While the Fazua motor appears to trump the Bosch motor, it's not that clear cut as Fazua's marginally bigger 430Wh battery means the overall system weight is actually around 200g more in total.

Bosch has paired the new Performance Line SX motor with a new CompactTube 400 battery which features new cell technology for higher energy density. Bosch says the new motor is the lightest battery in the Bosch Bike portfolio that can be integrated into the frame downtube. There is also the new PowerMore 250 range extender (approx. 1.6kg, 250Wh), increases assisted riding range by more than 60 percent in conjunction with the CompactTube 400 for riders looking to head out for a big day on the trails.

Bosch Performance Line SX lightweight motori being ridden on gravel

Bosch Performance Line SX lightweight motor is aimed at e-gravel too (Image credit: Bosch)

Bosch has added a new mode as well. The new ‘Sprint’ riding mode that will give riders an additional boost on steep sections or when you need some extra acceleration. Shown as ‘SPRNT’ in the display, this new mode will give a disproportionately higher power output for high-cadence sections.

Bosch has also added a new larger display, the Kiox 500, which has a 2.8in screen, although they recommend using the smaller Kiox 300 with the Performance Line SX system. Both Kiox models will also get a software update which will offer riders the ability to customize their displays. There is also a new Purion 200 controller which features a color display and can display useful stats like battery charge percentage, riding mode, time, and total distance. If you run it alongside a Kiox display you can utilize both screens, showing mapping on the Kiox and motor functions on the Purion.

Bosch hasn't provided specific dates for when the new motor and features will be available but there is a rough timeline. As soon as summer 2023 we should start seeing the Performance Line SX motor with sprint mode, the CompactTube 400 battery, the new Purion 200 controller, Kiox 500 display with customizable layouts. There will also be a new portable 2A Charger as well.

In fall/autumn 2023 we can expect to see the release of the PowerMore 250 battery extender, a mini Remote for Dropbar bikes, and a DualBattery function for selected batteries in the smart system range. Pricing is still TBC.

Graham Cottingham
Senior reviews writer, Bike Perfect

Graham is all about riding bikes off-road, based in Edinburgh he has some of the best mountain biking and gravel riding in the UK on his doorstep. With almost 20 years of riding experience, he has dabbled in downhill, enduro, and gravel racing. Not afraid of a challenge, Graham has embraced bikepacking over the last few years and likes nothing more than strapping some bags to his bike and covering big miles to explore Scotland's wildernesses. When he isn’t shredding the gnar in the Tweed Valley, sleeping in bushes, or tinkering with bikes, he is writing tech reviews for Bike Perfect.

Rides: Cotic SolarisMax, Stooge MK4, 24 Bicycles Le Toy 3, Surly Steamroller

Height: 177cm

Weight: 71kg