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since 2003

Mountain Bikes

Haibike SDURO HardSeven 4.0

  • Frame type


  • Yamaha PW mid-engine 250 Watt Drive Unit

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

  • Yamaha LED display

  • 9-speed Shimano Acera gears

  • Impact-resistant plastic SkidPlate

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The HardSeven 4.0 hard tail electric bike for 2017 is the entry level model within the Haibike sDuro range. The HardSeven 4.0 2017 eBike is built on cost effective components without compromising quality. Packing forks with 100mm of travel, this It is designed for the eMTB'er who wishes to take on some of the local trails. It is suitable for XC / Trail use. This e-bike also be used as a clutter free commuting 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 exceptionally 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 e-bike systems for sporty use. 

The Yamaha LED display is a compact yet robust display and a 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 e-bike 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 centrepiece 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 Alu 6061, Hydro Formed, Gravity Casting Interface
Motor Yamaha PW Crank Drive 36V 250 Watt. 100 - 280% Assist, 80Nm
Battery Yamaha Lithium Ion 36 Volt, 400 Wh, with BMS Management
Display Yamaha LED 3-Way Digital Main Display Switch
Forks SR Suntour XCM RL, 100mm
Brakes Tektro HD-M285 180mm
Shifters Shimano Altus Rapid Fire 9 Speed
Rear Mech Shimano Acera 9 Speed
Cassette Sram PG920, 11-34 Teeth, 9 Speed
Chain KMC X9 9 Speed
Wheelset XLC Disc Hubs on Rodi FW Rims QR
Tyres 27.5" x 2.25”(50-584) Schwalbe Smart Sam
Handlebars Haibike sDuro Bar 31.8mm 720mm
Stem Haibike TheStem 31.8mm
Headset A-Head, Alloy, Tapered
Seatpost Alloy Straight Post, 31.6mm
Saddle Selle Royal Voga
Weight 21.4 kg
Max speed  17mph assisted
Range 25-55 miles average

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