Are you in the market for a super lightweight electric bike crafted with cutting-edge materials? The Urtopia Carbon One Step Through (Carbon 1 ST) aims to offer just that—a carbon fiber eBike designed for urban commuters who value efficiency, quiet performance, and advanced technology. In this review, we’ll explore everything from its build quality and components to its ride performance, tech features, and overall comfort.

Carbon Fiber Construction: Industry-Leading Lightweight Design

One of the defining features of the Carbon 1 ST is its frame, made entirely from advanced carbon fiber, the same material used in Formula 1 and aerospace vehicles. This results in an incredibly light total weight of just 36 pounds, making it one of the lightest eBikes on the market.

Class One eBike with Pedal Assist Only

The Carbon 1 ST is categorized as a Class 1 eBike, meaning it does not have a throttle and assists you only when you pedal. It offers three levels of pedal assist controlled through a sophisticated torque sensor on the crankset, allowing a smooth, responsive boost up to 20 mph (and up to 25 mph if you unlock the turbo mode).

Motor and Battery Details

• Motor: A rear hub, 36V 350W motor peaks at 700 watts with 65 Nm torque. Utopia claims it is the lightest motor globally, weighing just 2.6 lbs.
• Battery: Integrated into the down tube with a sleek cover to blend seamlessly into the frame. The 36V 9.8 Ah battery delivers 352.8 Wh and takes approximately 2.5 hours to charge fully via a powerful 4-amp charger. You can easily remove the battery using a key lock system for off-bike charging.

Drivetrain and Brakes

The bike includes an 8-speed Shimano Altus drivetrain with an 8-speed trigger shifter and a 44-tooth single chainring. Stopping power is ensured by Tektro two-piston hydraulic disc brakes paired with 160mm rotors, for reliable, strong braking in various conditions.

Wheels and Tires

The Carbon 1 ST rides on 700cx 40C Kenda tires with an aggressive gravel tread pattern. The front fork is also carbon fiber, featuring a through-axle for rigidity and durability.

Size and Fit

The eBike measures 71 inches in length, and riders with heights between 5’1” and 6’1” can use it comfortably—though it especially suits shorter riders. The step-over height is a manageable 18 inches, making mounting and dismounting easy.

While the handlebar height adjustments are limited, you can add spacers in the headset to raise the stem slightly. The saddle height is adjustable with an Allen wrench, allowing for custom fitment. However, for taller riders around 5’9” and above, the bike may feel a bit compact or cramped.

Additional Design Features

• Plastic fenders to protect against road spray
• Flat plastic pedals with a grippy, textured surface
• Hidden seat post lock for security
• Battery-powered tail light for nighttime visibility
• Multiple mounting points on frame and fork for racks or accessories

Display and Control Pad

The Carbon 1 ST has a minimalist dot matrix display with a fingerprint sensor to power on the bike. The screen shows essential data like speed, pedal assist levels, trip distance, power output, battery status, and even weather updates.

Voice Commands and Audio Features

The Carbon 1 ST includes innovative voice commands such as adjusting the speed assist level, turning lights on/off, and locking the bike. It also features Bluetooth speakers for music playback via a connected phone app—though sometimes connectivity may require patience.

Smartphone App Integration

The companion app enhances the bike experience with features such as:

• Real-time navigation
• Remote control of lights and lock system
• Alarm mode activation
• Music control via Bluetooth speakers
• Personalized sound and vibration feedback settings
• Geo-fencing and service tracking

Comfort and Handling

The Carbon 1 ST excels at providing a comfortable upright riding position, with a medium-thick saddle that offers decent cushioning and minor shock absorption. Despite the lack of suspension, the frame’s carbon fiber build helps absorb vibrations well, and the tires provide good grip on gravel.

Pedal Assist and Power Delivery

The torque-sensor driven pedal assist feels natural and intuitive. At pedal assist level 1, the bike offers subtle help, which increases progressively through levels 2 and 3. Turbo mode significantly boosts acceleration and top speed, although the bike maintains a cruiser vibe rather than a speed demon’s thrill.

Battery Range and Charging

Utopia claims a range of up to 80 miles per charge under ideal conditions. Real-world use suggests a practical range closer to 19-21 miles when factoring in mixed riding conditions and hill climbs. The small, lightweight battery contributes to the limited range but enhances the bike’s portability.

Charging is straightforward, with fast recharging available via the removable battery and provided 4-amp charger, making daily commuting convenient.

Braking

The hydraulic disc brakes perform exceptionally well, providing quick and reliable stopping power, even at higher speeds of 20 to 25 mph. Tests show stopping distances of around 17 to 25 feet, reflecting the safety and control offered by the system.

Hill Climbing

The Carbon 1 ST handles moderate hills, including steep grades up to 18%, but it struggles with longer or more challenging climbs due to its smaller motor torque and limited battery capacity. Riders in hilly areas might find the power insufficient for continuous uphill rides.

Off-Road and Sand Performance

While primarily designed for urban and light gravel use, the bike’s aggressive tires make it capable on gravel paths with some discomfort due to the lack of suspension. The bike performs poorly in sand, though its extremely light weight allows easy manual handling when stuck.

Pros and Cons

Pros

• Ultra-lightweight carbon fiber frame and fork
• Smooth, quiet, and responsive pedal assist system
• Integrated, removable fast-charging battery
• Excellent hydraulic disc brakes with solid stopping power
• User-friendly smartphone app with voice commands and Bluetooth audio
• Sleek, minimalist design with multiple color options
• Comfortable seating position for shorter riders
• Fast charging and easy portability

Cons

• Limited size fit for taller riders (best for 5’1” to 5’6”)
• Small battery limits extended range, especially on hills
• No throttle option may require adjustment for some riders
• Display angle is fixed and reflective, potentially hard to read in sunlight
• Off-road and sand capability limited due to lack of suspension
• Bluetooth music playback can be finicky to connect

Who Should Buy the Urtopia Carbon One Step Through?

The Carbon 1 ST is an excellent choice for urban commuters and recreational riders who want a sleek, lightweight eBike with enough power and technology to make city riding enjoyable and efficient. It particularly suits shorter riders looking for a comfortable step-through frame and value a bike that is easy to carry, park, and charge quickly.

If your daily rides are mostly flat or gently rolling terrain and you prioritize a quiet, efficient ride over brute power or extended range, this bike fits perfectly. However, riders living in mountainous areas or seeking aggressive off-road capability should consider other options.

Final Thoughts

The Urtopia Carbon One Step Through breaks the mold for lightweight, high-tech eBikes with a carbon fiber frame and innovative integrated features. It combines performance, portability, and premium components into a stylish package that stands out in the crowded electric bike market.

While it has its limitations regarding rider height fit and half-day battery range, the ride quality, braking system, and app connectivity offer a superior user experience. At its current price point and with a 2-year warranty, the Carbon 1 ST represents a compelling option for those seeking a modern commuter bike with stealthy, silent operation and smart features baked into a transparent, intuitive platform.

Check the link below to see current pricing and availability, as market conditions may affect cost. Whether you’re new to eBikes or upgrading, the Carbon 1 ST offers an exciting glimpse into the future of lightweight carbon fiber electric bikes.