121mm Drum Brake Hub 1.4kg Smart Security Brake Hub Lock

ZS3704 is the rear-wheel version of the Lofandi 80 mm drum brake hub lock series. ZS3704 is the rear hub replacement version with 121 mm O.L.D. and 1.4 kg reference weight. It integrates the wheel hub, drum brake and smart electronic locking mechanism into one compact assembly for shared e-bikes, rental bicycles and fleet mobility platforms.

The product is developed for vehicle projects that need braking, anti-theft locking and electronic control in a single wheel module. It supports 5V DC / 48V DC vehicle electrical systems and can communicate with the main controller, IoT module or battery system through UART, RS485 or CAN.

The built-in Hall speed sensing structure uses a standard 4-magnet ring to support movement detection. Together with patented mechanical Anti-lock protection and customer-defined electronic protection speed, the lock helps reduce the risk of improper locking while the wheel is moving.

The complete unit reaches IPX7 waterproof protection and uses high-strength metal die-cast structural parts for outdoor fleet operation. OTA online upgrade support also makes the series suitable for connected shared mobility platforms that require remote management and future firmware maintenance.

• Rear Wheel Locking Solution: Designed for rear hub replacement and rear wheel anti-theft protection.
• Integrated Drum Brake Hub: Combines 80 mm drum brake, hub structure and smart locking mechanism.
• Smart Electronic Control: Supports control through the main controller, IoT module or battery system.
• Multi-Protocol Support: Compatible with UART, RS485 and CAN communication.
• Speed Sensing Support: Standard 4-magnet ring design supports movement status detection.
• High Structural Strength: Main axle load strength reaches 300kgf.
• IPX7 Waterproof Protection: Suitable for outdoor fleet and shared e-bike use.
• Rear Mobility Integration: Suitable for shared bikes that require rear-side braking and locking layout.

The ZS3704 rear drum brake hub lock integrates braking, locking and speed sensing into the rear wheel structure. When connected to the vehicle controller, IoT module or battery system, the lock can receive electronic commands and perform lock or unlock actions according to vehicle-side logic.

The speed sensing system uses a standard 4-magnet ring configuration, which helps provide wheel movement information to the vehicle control system. This supports electronic protection speed settings that can be defined according to customer requirements.

As a rear wheel product, ZS3704 is suitable for vehicles where rear-side locking offers better structural matching, improved anti-theft strategy or more convenient integration with the rear brake system. Compared with the front version, its 121 mm O.L.D. and 1.4 kg reference weight reflect its rear wheel application positioning.

• Smart rear drum brake hub lock for shared bikes and e-bikes.
• Replaces the rear hub and integrates with the rear wheel assembly.
• 80 mm drum brake structure for compact rear braking design.
• 121 mm O.L.D. for rear wheel hub compatibility.
• 36H13G spoke specification.
• M12 * 1.25 axle specification.
• Supports 5V DC / 48V DC vehicle electrical systems.
• Compatible with UART, RS485 and CAN communication.
• IPX7 waterproof rating for outdoor fleet use.
• Suitable for shared bicycle fleets, rental e-bikes and rear-wheel security platforms.

ZS3704 is suitable for shared bikes, e-bikes, rental bicycles and urban fleet vehicles that require rear wheel locking and drum brake integration. It is especially useful for platforms where the rear wheel is the preferred locking position for anti-theft, frame matching or braking system design.

For fleet operators, the integrated rear hub lock can support remote control, speed sensing and durable outdoor operation. For OEM brands, the product helps combine rear braking, wheel hub structure and smart locking into one module, reducing separate component complexity and improving vehicle-side integration.