Tested: The Cube Supreme Hybrid Deluxe SLX 600 – Ultimate Urban E-Bike with ABS and Automatic Gearbox

In France, Cube may be less known for its electric bikes compared to its presence in Germany, particularly in road and mountain biking. However, its range is extensive, especially in urban models, including the Supreme Hybrid SLX 600 which we had the chance to test.

On paper, this electric bike (E-bike) is fully equipped, featuring dual suspensions for added comfort, braking supported by ABS, all powered by a Bosch PX drive system. Moreover, the package is attractively priced just over 4,000 euros! Could this be the perfect urban model? Here’s what Frandroid thinks after 150 km.

Technical Specifications

This review is based on a model loaned by the brand.

Sleek Design for an Urban E-bike

The Supreme Hybrid boasts an elegant design. While the open frame shape is traditional and practical for daily use, the finish is impressive. Cube opts for invisible welds covered by a matte gray-blue paint with beautiful reflections. The brand integrates most of the cables – except for the front brake and lighting – for a cleaner look, though the battery cover remains black plastic, which is slightly disappointing.

Integration is also limited on the handlebar for easier access in case of issues, while the stem is angle-adjustable. This allows for a more or less forward riding position, depending on the rider’s height. The front light is very powerful – 150 lux / 600 lumens – with a broad and long beam, providing excellent visibility even on unlit roads, while the bright rear light features a brake light for added safety.

Over 30 kg but Fully Equipped

The electric bike is also equipped with metal mudguards that wrap nicely around the sides, extended at the front, while the dual belt cover minimizes splashes. The wide-foot kickstand provides good stability, and the wheel lock secures the bike during short stops. The rear carrier is also present, supporting up to 25 kg with a spring flap, but only compatible with RIlink (for ACID panniers) attachments.

The only disappointment with the Cube Supreme Hybrid SLX 600 is its inability to accommodate a front rack due to the lack of fixtures. The accessories increase the weight to 30.2 kg in size 50 (equivalent to M) according to our measurements, which is more than the announced 29.5 kg. The total load capacity is 140 kg, with a maximum of 110 kg for the rider.

Well-integrated Bosch System

Equipped with a Bosch drive system, the Cube Supreme Hybrid features the Bosch Smart System. It includes the largest Kiox 500 display with a 2.8-inch diagonal, allowing clear visibility of all possible data scrolled through with the remote control on the left: speedometer, distance, remaining range, ABS activations, etc.

The electric bike is thus connected to the eBike Flow app, where one can find features already seen in previous tests. It can automatically lock when removing the display, adjust or select modes to your liking, or even review your recorded trips. Paid features through Flow+ can add an alarm, GPS tracker, Battery Lock, as well as extended navigation info.

Refined Comfort

The VAE Cube’s geometry encourages a more passive, upright position for the cyclist. For our height of 1.84m, size 50 (M) is a bit limiting, necessitating a raised seat and an advanced stem. In this scenario, we recommend a size L to maintain comfort, as the parallelogram suspension is designed to absorb body weight. The front pneumatic fork SR Suntour NCX32 adds comfort over small obstacles and on paths, but does not make the Supreme Hybrid a true all-terrain model with its limited travel (50 mm).

The Schwalbe Marathon tires, designed for urban environments, provide excellent grip, even in the rain. They enhance the braking, managed by the classic Shimano MT200 hydraulic disc brakes with dual calipers and 180 mm discs, all paired with an ABS system. We recorded very short stopping distances, under 3 meters at 25 km/h, and 1.10 m at 15 km/h.

The ABS has proved invaluable in some situations during wet rides and on paths. Having this feature as standard is a significant plus that’s rare enough to highlight.

Not Very Agile but High-Performance with Automatic Transmission

However, agility is not a strong point, due to the riding position, and one does not push too hard on turns due to a frame that is very, or even too, flexible, which tends to twist easily. However, this does not hinder the performance provided by the central Bosch PX motor, which offers superb acceleration and restarts, all with a welcome smoothness (vs the more nervous CX).

We continue to appreciate the responsiveness of the torque sensor, the natural pedaling feel, while the noise remains relatively contained (a slight high-pitched whistling in the forest, but barely audible in the city). It is precisely in urban areas that the Cube Supreme Hybrid excels with its automatic transmission by Enviolo variator. Once your preferred cadence is saved, the E-bike continuously adjusts to this throughout speed variations, with minimal latency on startup.

High Consumption but a Battery that Guarantees a Minimum of 60 km

Cube equips its urban electric bike with a 600 Wh battery. Without a theoretical range specified by the German brand, we thus had to determine the possible range in different modes. In the most vigorous Turbo mode, we managed 63 km on a full charge, which is quite good at an average temperature of 16°C, including some rain.

In Auto mode, the Cube averages around 75 kilometers, and approaches 85 km in Tour+. The Eco mode exceeds 100 kilometers of range, still around 15°C, in urban settings and on mild inclines. As usual, a slight loss of performance is noticeable under 10%, even more so under 5%. It is possible to reach 0% with still a bit of juice left, enough to reach your destination without too much effort.

It is very easy to check the battery level, thanks to the percentage displayed continuously, with a window indicating the remaining (theoretical) autonomy depending on the modes.

A 7-hour Recharge with the Provided Charger

Once depleted – where it is advised not to regularly go below 10% to extend the battery’s life – the battery can be charged either on the bike or separately. Removable under its easy-to-remove cover and protected from the weather lock, the Bosch Powertube 600 weighs 3.07 kg, but is very long and lacks a carrying handle.

To recharge it, the provided charger is the standard 2A, but we had the optional rapid 4A charger. Like other Bosch E-bikes, the initial charging phase is unusually fast – at least on the display – with 20% regained in 25 minutes. It then stabilizes after 30%, with half a charge in 1h40, 80% in less than 3 hours, and 100% in 3h30. Thus, the time is doubled for the standard charger. The charge percentage is visible on the display if charging on the bike (or on the app), while the battery has 5 indicators for mobile recharging.

A Highly Equipped Model in an Extensive Cube Catalog

The Cube Supreme Hybrid Deluxe SLX 600 is part of the latest generation of urban electric bikes, launched in late 2025. This model is just one among many Deluxe models in the catalog, starting at 3,199 euros. Our test version, available only in an open Easy Entry frame, is priced at 4,099 euros in 4 sizes (46, 50, 54, and 58), but only in one color.

For even more performance (Bosch CX up to 120 Nm), a rapid charge (4A), the SLT 600 is priced at 4,799 euros. In contrast, the “PRO 600” variant loses the ABS and settles for the Bosch Performance Line (75 Nm) at 3,599 euros, while the Deluxe One 600 features a Nexus 5-speed hub and a Bosch Purion 200 display. Worth noting, the Comfort models are more affordable (starting at 2,649 euros), but with a spring fork, a classic suspended seat post, a chain drive, and Continental tires.

The German brand guarantees its electric bikes for 2 years, including the electric assistance, with an extended 6 years on the frame. It has a network of 300 partner dealers in France, capable of providing after-sales service.