Bosch calls the all-new CX-R its highest quality ebike drive unit to date, high self-praise from one of the world's largest ebike drive suppliers. The new magnesium-housed motor cranks torque and power to the top of the lineup and adds a new top speed "race" mode for getting fired up on all cylinders in a hurry. It might just inspire a new generation of fast, fully adrenalized electric mountain biking.
Bosch's new Performance Line CX-R drive picks up where the Performance Line CX leaves off, increasing peak power from a 600-W ceiling to a full 750 watts. Torque gets boosted from 85 to 100 Nm (74 lb-ft), while maximum assistance level rises to 400 percent, a target Bosch set with steep technical hills in mind.
The CX-R motor weighs in over 3 oz less than the standard CX at an even 6 lb (2.7 kg), thanks to its combination of powder-coated magnesium shell, corrosion-resistant titanium crank spindle, and ceramic ball bearings.
The new CX-R earns its "R" with an exclusive Race mode that directs full motor power into all-out lag-free acceleration, right up to top speed and/or 400% assistance level. Race mode also extends time on the integrated boost function that increases output to help the rider power over and through large obstacles, such as an oversized rock garden or tangled web of tall, slick tree roots. It promises to turn short hike-a-bike jaunts into just another part of the ride.
A new eMTB+ mode essentially splits the difference between the existing range-optimizing eMTB mode and all-out Race assistance. It works to harness the new levels of power and torque more naturally into the riding curve, responding in line with changes in the rider's own power and cadence. A pair of integrated sensors measures pedal input 1,000 times per second to ensure immediate drive response the rider doesn't even notice beyond the overall smoother performance.
Riders can also fine-tune Ride and eMTB+ settings in Bosch's eBike Flow app. To better illustrate how this works, one of Bosch's latest videos shows stuntman-level pro mountain biker Danny MacAskill dial torque and power up to maximum in order to navigate a particularly tight switchback. The extra oomph helps him muscle up a short, steep rock stack after coming to a virtual stop on a hop-turn. Increasing output on-demand helps in this case to grind through a short but difficult momentum-sapping stretch that would otherwise require hopping off and walking. It can then be dialed back to help extend battery life and range.
"The new eMTB+ riding mode brings the power of the CX-R to the trail in a controlled manner," explains Claus Fleischer, CEO of Bosch eBike Systems. "Thanks to Dynamic Control – a type of traction control in the new mode – propulsion remains controlled even on demanding terrain, steep sections and wet surfaces."
The CX-R also comes with the new Kiox 400C, a top tube-integrated display that auto-adjusts to ambient light and also adjusts the data shown based on riding situation. For instance, a data set that includes elevation is displayed when pedaling uphill, switched to a speed-focused display on the way down. Of course, riders have the last say in what data they're looking at and can either adjust settings ahead of time in the eBike Flow app or on-the-fly with the physical buttons on the screen or handlebar remote.
No pricing just yet, as the CX-R mid-drive will come directly with OEM ebikes built around it. Bosch expects the first of those to hit the market in Fall 2025. We'll keep an eye out for the first CX-R bike debuts when Eurobike gets underway in late June for a better idea of how the boosted CX-R specs will affect numbers like range and battery life.
Good news for current Performance Line CX owners, who need not seethe with envy: Bosch also announced this week that the latest Performance Line CX motor (BDU384Y) will be upgradable to the CX-R's 750-W/100-Nm/400% stat line via an OTA eBike Flow app update. It won't receive the CX-R-exclusive Race mode but will get the eBike+ mode.
The catch? The individual bike manufacturer has to approve the over-the-air update ahead of the July rollout. Each manufacturer serves as the final authority on specs and updates, but we can't imagine many eMTB builders falling behind the pack by not approving a performance boost that's sitting out there like sumptuous, low-dangling fruit.
We're generally big proponents of traditional non-electric pedaling, but watching videos like Bosch's CX-R promo always makes us want to give a few eMTBs a thorough long-term shakedown.
Source: Bosch
