The fundamental differences in drive logic directly distinguish the two types of electric bicycles: The motor output of pedal assist bike (Pedal/Torque sensing assisted bicycle) is strictly synchronized with the force or pedal frequency applied by the rider on the pedal. Under the EU EN 15194 standard and the US Class 1/Class 3 classification, The upper limit of its speed assistance is set at 25 km/h or 45 km/h (in specific markets such as the Class 3 in the United States), which means that the assistance power will be cut off 100% unless the rider pedads actively. On the contrary, Throttle e-bikes (such as the Class 2 in the United States) allow users to obtain immediate power propulsion within the range from 0 km/h to 32 km/h (the speed limit in the United States) through pure throttle, without any stepping action. This fundamental difference in operation mode profoundly affects energy consumption efficiency, regulatory compliance and riding experience.
Energy efficiency data reveal significant differences: An energy efficiency test conducted by the European Cycling Organization (ECF) found that under the same 15-kilometer urban commuting route and a load of 75 kg, The average power consumption of the pedal assist bike (equipped with the Bosch Performance Line CX mid-mounted motor) is only 4.8 Wh/km, while the electric vehicle equipped with a 750W hub motor and throttle consumes 7.2 Wh/km. The difference in energy consumption efficiency is as high as 33%. This is directly attributed to the design of the auxiliary system: The torque-sensing pedal assist bike detects the force applied by the rider’s leg muscles in real time during the ride (the sensor accuracy can reach 0.1 N·m), and the motor only outputs an auxiliary power that matches 20%-300% (with adjustable levels) of the rider’s force application intensity. However, due to the lack of a closed loop of the rider’s power input for throttle operation, the motor will bear 100% of the power load. Choosing the pedal assist bike can achieve an actual commuting distance of more than 100 km with a battery capacity of 500 Wh (test conditions: ECO mode, medium assistance level), while the pure throttle model of the same capacity often reduces the distance to less than 65 km under high-intensity use.
The regulatory framework clearly distinguishes between the two types of products: In the EU market, according to the EPAC (Electrically Pedal Assisted Cycle) regulation EN 15194, a legal pedal assist bike must have its power completely cut off and rely on pedal input at a speed of 25 km/h. The upper limit of the continuous rated power of the motor is 250W. In the United States, Class 2 electric bicycles that are allowed to use the throttle must limit the maximum motor output to 750W, and the full throttle control can reach 32 km/h. Regulatory differences profoundly affect product access: 22 European countries, including the United Kingdom, Germany and the Netherlands, prohibit pure throttle vehicles without pedal functions from being used on public roads (except for specific modified models for the disabled). Regulatory enforcement incidents have sparked controversy. For instance, in 2021, the Berlin police seized 600 imported throttle electric vehicles that did not meet EU standards. In the US market, although pedal assist bikes and throttle bikes share Class 1 or Class 2 license plates, urban management tends to be differentiated – several metropolitan areas such as San Francisco and Denver have introduced regulations to impose speed limits of ≤24 km/h or usage time restrictions on pure throttle operation modes in some bike lanes.
In terms of the user experience dimension, the two modes bring completely different physiological feedbacks during cycling: Professional biomechanical research (Journal of Sports Sciences) points out that under the conditions of an average heart rate of 130 bpm and a speed of 22 km/h, pedal assist bike (medium-level assistance) can enable the leg muscle group activity intensity (EMG detection) of cyclists to reach 75-85% of that of pure manual cycling. It not only reduces cardiovascular pressure (heart rate is 25% lower than that of pure manual cycling), but also retains the basic fitness benefits. For cyclists operating with the accelerator, due to the almost disappearance of leg muscle activity (the EMG data is only 5% of that of the pure manual mode), the measured calorie consumption after the 10-kilometer journey can be as low as 120 kcal. It is much lower than 230 kcal for pedal assist bike riding (difference >90%), and there is a risk of muscle degeneration with long-term use. A cycling preference test conducted by the laboratory of Nijmegen University in the Netherlands on 60 participants showed that 72% of commuters preferred the natural assistance mechanism of pedal assist bike and evaluated the “smooth, tradition-like cycling” experience it brought. The users who mainly rely on throttle operation are mostly elderly people with limited mobility (over 60 years old), accounting for 18% of the sample.
There is also a gap between maintenance costs and system complexity: The throttle system relies on the opening signal of potentiometers or Hall sensors to achieve linear throttle travel control from 0 to 100%. The average time between failures (MTBF) of such electronic throttle components is approximately 5,000 operation cycles, and they are prone to moisture failure in an environment with a humidity higher than 65%. The torque/pedal frequency sensing system of pedal assist bike (such as Shimano STEPS DU-E8000) has a sensing element sealing grade of IPX6 and an anti-vibration standard deviation exceeding 1.5g RMS. The average service life exceeds 15,000 riding hours. The operation and maintenance data of BIKETOWN, a shared operator in Portland, confirmed that the frequency of fault reports for pure throttle vehicles was 2.3 times that of pedal assist Bikes. The main problems were concentrated on the distortion of the throttle signal (with an incidence rate of 28%) and the excessive wear of the braking system (a 37% reduction in the brake disc replacement cycle), attributed to the additional 150 N·m impact on the braking load caused by the high-frequency full-throttle start.
In terms of power output characteristics, the throttle control motor has a steeper starting torque slope: under a typical 500W hub motor configuration, a peak torque of 0→95% (80 N·m) can be achieved within 0.3 seconds after the throttle travel starts, making it suitable for high-load scenarios such as starting on slopes. The pedal assist bike requires the pedal frequency sensor to be ≥15 RPM or the torque sensor to detect that the foot force is greater than 10% of the pedal travel before activating the assistance. The initial acceleration response time is approximately 1.5 seconds. However, it performs better in cruise stability. For instance, Bosch’s smart eBike system generates motor power fine-tuning instructions 1,000 times per second based on pedal input to keep the speed fluctuation within ± 0.5 km/h (such as when the test section contains a 5% slope change). However, traditional throttle control requires frequent manual intervention of the throttle opening, which can easily lead to a speed drift of ±3 km/h.
Therefore, pedal assist bike not only defines the technical boundaries of the riding experience – such as retaining more than 70% of the basic movement benefits and more coherent road feel transmission, but also its feature of complying with the regulations of major developed markets (coverage rate > 85%) avoids the usage risks; While throttle electric vehicles offer critical convenience in specific groups (patients with limb dysfunction) or scenarios (dense logistics on slopes), they are constrained by a 32% higher unit energy consumption and more severe compliance challenges, making their position in the evolution of urban planning policies more cautious.