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Mountain Bikes

Haibike SDURO HardFour RX Kids

  • Frame type


  • Yamaha PW mid-engine 250 Watt Drive Unit

  • Yamaha battery, 36V, 400Wh, lithium ion

  • Yamaha LED display

  • Impact-resistant plastic SkidPlate

  • 9-speed Shimano Acera gears

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The SDURO HardFour is a revelation for families who want to ride together and a powerful alternative for the school run. Compared to this bike, a PlayStation totally loses its appeal! The Haibike Sduro uses powerful Yamha PW drive system that integrates the motor in a compact manner without separate mounting plates that decreases the visual volume of the engine.

Read Riding to school on an electric bike

The Yamaha PW mid-engine Drive Unit is proven to be a powerful and reliable motor. Thanks to its Zero-Cadence system, it supports the rider from the first revolution of the crank. The PW unit by Yamaha has an eceptionaly quick power delivery. As one of the few motors available allowing a dual chainring, the Yamaha system is able to offer a broad range of gears providing more gear options out on the trails. Given its high maximum torque of up to 80Nm, its compact size, and its low noise, the Yamaha PW is one of the best eBike systems for sporty use. 

The Yamaha LED display is a compact yet robust display and remote unit. Despite its small size, it provides the rider with all essential information. The actual LCD display area is large on the Yamaha system, each unit is easy to navigate and user friendly. The units are displayed in a clear, easy to read manner. Positioned on the left of the handlebars, the remote is easily accessible.


Impact-resistant plastic SkidPlate, similar to a helmet, the SkidPlate protects the motor from damage and is strong enough to absorb even the hardest of strikes that would otherwise damage the motor. Conventional eBike motors sit low in the frame and run the risk of being damaged by strikes to the underside of your bike. In 2012 Haibike introduced the SkidPlate, a simple protective element that effectively protects the motor from below.

The centerpiece of the frame: the motor interface. At this connection point many important functions come together: the engine mount, swing arm and shock mounts, and the battery and downtube connection. The more stable the interface is, the more stable the entire frame is.

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Technical Specifications

FRAME    aluminium 6061, Gravity Casting Interface, hydroformed, quick-release 5 x 135mm, disc brake Post Mount
DRIVE UNIT    Yamaha PW-System, 250W, 25km/h
BATTERY    Yamaha Lithium Ion, 400 Wh
CHARGER    Yamaha quick charger 4A
FORK    SR Suntour XCR LO Lockout, air/oil, Travel: 63mm, aluminium steerer tube 1 1/8", quick release
SHIFTING SYSTEM    Acera M3000, 9-speed, Shimano
GEAR SHIFTER    Shimano Altus M370, rapidfire
REAR SPROCKET    Sram PG920, 11-34 teeth
CHAIN WHEEL    FSA steel, 32
CHAIN GUIDE    Nylon directmount
BRAKE LEVER    Tektro HD-M286, aluminium
FRONT BRAKE    Tektro HD-M286, aluminium, 160mm
REAR BRAKE    Tektro HD-M286, aluminium, 160mm
TIRES    Schwalbe Table Top Performance, 57-507
RIMS    Rodi FW Disc, with eylets, hollow rim, aluminium
FRONT WHEEL HUB    XLC aluminium disc, quick release axle
REAR WHEEL HUB    XLC aluminium disc, quick release
SPOKES    Sapim Leader, black
HANDLEBAR    Haibike Components TheBar Topflat 640mm
GRIPS    XLC lock on grips Sport
STEM    Haibike Components TheStem , A-Head, Bar bore: 31.8mm, 12%u02DA
HEAD SET    A-Head Tapered
SADDLE    Selle Royal Hello
SEAT POST    Haibike Components TheSeatpost , Patent, 31.6mm
PEDALS    Wellgo LU984DU
WEIGHT    18.9kg
MAX SPEED  17mph assisted
RANGE 25-55 miles average

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