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Description
This Bike Is Now Sold Out
This electric bike is now sold out for the year. Please click here for the latest, in stock models.
We will leave this page here for past reference to specification on this model.
Keep scrolling down for the original spec. These listings will not be updated moving forward.
Who is this bike suitable for?
This one's pretty obvious - It's for kids who require that little bit of assistance! This 24" wheeled unisex kids electric bike is suitable for children ranging from the age of 9 onwards. A kids specific chassis and refined Yamaha eBike system.
The SDURO HardFour is a revelation for families who want to ride together. Compared to this bike, a PlayStation totally loses its appeal! - Enduro Magazine
New Features
Welcome to the sDuro HardFour 4.0 2017, finally we have a 24" kids electric bike. Do your children get fed up and tired mid way through the ride?
Do you want to ride further with your family? Or does your child require some support?
The new Haibike sDuro HardFour 4.0 2017 is the answer!
The sDuro HardFour offers refined kids geometry and a smaller 24" wheel. Suitable for boys or girls with an average age of 8 onward.
This simple spec'd bike is great for children and Haibike have included a refined version of the 2017 Yamaha system, learn more further down the page.
The 2017 sDuro HardFour 4.0 features a 9 speed Shimano Acera / Altus gear system with simple to use trigger shifters to give the kids full versatility across varied climbs and descents. Remember with crank drive you can use the gears with the assistance.
The smaller 24" wheels offer kids full control and stability. Small enough to manoeuvre around, but big enough to take on a full day's ride and follow the parents through varied terrain.
Although kids sized wheels, Haibike have built them with decent disc hubs and double wall rims.
On the 2017 sDuro HardFour 4.0 we see the Tektro hydraulic disc brakes. Simple to use and fairly maintenance free, it's a good option on this 24" kid's bike. With the electric assistance we want to ensure braking power remains solid.
Thrown into the mix are a set of 24" Schwalbe Table Top tyres. Both lightweight and durable in their construction, they allow a faster rolling resistance while maintaining grip at the same time.
A good choice for a mixture of surfaces.
We are excited about this bike, a proper German crank drive Yamaha eBike. Finally you can take the kids on a full ride out without the stresses and strains of them getting worn out after a short distance. Ultimately this equals more ride time, more ride time = more fun. It's a winner all round!
Yamaha eBike System
The new Haibike sDuro HardFour 4.0 is powered by the latest Yamaha electric bike system. Haibike has partnered with Yamaha to bring a brand new line of sDuro eBikes, this 250w motor offers up to 280% assistance and peaks at 60Nm of restricted torque (on this kids version).
The assistance is set in 3 levels on the kids version - 'Eco', 'Standard' & 'High'. This allows the child to fine tune the amount of assistance required. We also see a new set of controls that loose the LCD screen in replace of simple on / off power and assistance, easy to use buttons.
The Haibike sDuro Hard Four 4.0 2017 eBike is offered with the 400Wh Yamaha battery to give a full day's ride time. Now your son / daughter can join you for the longer rides too!
On the Kids version the assistance speed is lowered down to 12.5mph. We want children to have fun whilst maintaining a safe pace. We also remove the walk assist and simplify the levels to make it as user friendly as possible.
You can learn more / read reviews of the Yamaha eBike system on our blog pages.
Whats included?
This electric bike comes fully set-up by our workshop technicians. You can be sure that every aspect of the eBike has been dialled in for optimum performance. All our electric bikes arrive with a user manual, keys, charger & free follow up service within 3 months.
Our electric bikes also include a 5yr warranty on the frame, 2yr warranty on all the electrics & 1yr warranty on the components. In the event of a problem, we handle all warranty claims in-house. We can also offer worldwide support.
E-bikeshop is a UK Yamaha Electric Bike Service Center and our in house workshop is now exclusively reserved for our own eBike customers. We also have parts / spares to hand should they be required.
*Range is dependant on many factors inc rider weight, wind, hills, terrain etc. For a better estimate, please use our range calculator.
Specifications
General Bike Specifications
Frame Alu 6061, Hydro Formed, Gravity Casting Interface
Forks SR Suntour XCM LO, 63mm
Rear Shock N/A
Brakes Tektro HD-M286 160mm
Shifters Shimano Altus Rapid Fire 9 Speed
Rear Mech Shimano Acera 9 Speed
Cassette Sram PG920, 11-34 Teeth, 9 Speed
Chain KMC X9e 9 Speed
Wheelset XLC Hubs on Rodi FW Rims QR
Tyres Schwalbe Table Top 24 x 2.25
Handlebars Haibike sDuro Flat Bar 31.8mm 640mm
Stem Haibike TheStem 31.8mm
Headset A-Head, Alloy, Tapered
Seatpost Alloy Straight Post, 31.6mm
Saddle Selle Royal Hello
Weight 18.9 kg
Electric Bike Specifications
Battery Yamaha Lithium Ionen 36 Volt, 400 Wh, with BMS Management
Display Yamaha LED 3-Way Digital Main Display Switch
Motor Yamaha PW Crank Drive 36V 250 Watt. 100 - 280% Assist, 60Nm
Range 30 - 80 miles of power assisted range, depending on terrain
E&OE