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UK supplied configuration:
250W power limit · 15.5mph Max Speed
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This model is supplied restricted to 250W and 15.5mph (25km/h), which is why bikes like this are commonly described by retailers as road legal when kept restricted. However, the Department for Transport takes a stricter view of e-bikes that can be configured to provide assistance above the EAPC limits, even if they are supplied restricted and remain in that configuration. We therefore recommend reading our UK E-Bike Road Use Guide before using it on public roads.
🔧 Bike setup & first ride
Boxed delivery — some final assembly and safety checks needed.
Your bike will arrive
boxed and approximately 80% assembled.
Some final assembly, adjustment and safety checks
will be needed before your first ride.
Depending on the model, this may include fitting or
checking the handlebars, stem, pedals or wheels,
checking tyre seating and pressures, adjusting
brakes and gears, and checking other safety-critical
components.
Please follow the manufacturer's instructions supplied
with your bike and make sure all required assembly,
adjustments and safety checks have been completed
correctly before riding.
If you're not confident carrying out the setup or checks
yourself, we recommend asking a competent bicycle
mechanic or suitably trained cycle professional to help.
You're responsible for making sure the bike is correctly
assembled and safe to ride before first use. Problems
caused or contributed to by incorrect assembly,
adjustment or missed safety checks may not be covered
as product faults.
✔ Stands out for: 48V 15Ah battery, 20" x 4.0" tyres and folding frame
✔ Better than most for: rough local roads, light trails and riders wanting fat-bike stability for less
✖ Trade-off: steel frame and basic disc brakes keep it affordable, but not especially light or refined
At a glance
THE ESSENTIALS
Conservative range28–52 miles
Motor torque40Nm
StorageFolding design
Rider height165–195cm
TyresFat tyre design
Hill capabilityLow
Conservative range is an estimate; actual distance varies with terrain, rider weight and assistance.
About the Koolux BK6S 4.0 Folding E-Bike
Take on any terrain with the Koolux BK6S 4.0, a powerful fat-tyre e-bike designed for riders who crave freedom and performance. Equipped with a robust 250W motor and a high-capacity 48V battery, the BK6S 4.0 delivers impressive range and reliability - perfect for everything from city commutes to off-road trails.
The 4.0-inch wide tyres provide exceptional grip and stability on sand, snow, gravel, and tarmac, while front suspension ensures a smooth, controlled ride over bumps and rough ground. With its rugged frame, responsive disc brakes, and bold styling, the Koolux BK6S 4.0 is ready to take you further, no matter where your journey leads. Ride harder, explore more.
Specifications
Gears: 7 Speed
Frame Material: Steel
Power Supply: Lithium battery
Wheel Size: 20″
Tyre Width: 20" x 4"
Braking System: Disc Brake
Battery Capacity: 15Ah
Charging Time: 5-6 hours
Range per Charge: 45-95km
Engine Position: Rear Hub Motor
Torque: 30-50 Nm
Battery Position: Down Tube
Max Assisted Speed: Up to 25 km/h (15.5 mph)
Battery: 48V 15Ah lithium battery
Max Load: 120kg
Motor Power: 250W
Net Weight: 33.2kg
What's Included
Battery x 1
Battery Charger x 1
16 in 1 Simple Tool x 1
Quick Operation Guide x 1
User Manual x 1
Bicycle Locks x 1
Bicycle Pump x 1
Sizing Guide
A. Total Length: 168 cm
B. Handlebar Height: 115-128 cm
C. Wheelbase: 115 cm
D. Standover Height: 83-106 cm
E. Top Tube Length: 60 cm
F. Wheel Diameter: 20"
G. Handlebar Length: 58 cm
Folded Size: 96 x 38 x 75 cm
Rider height: 165-195 cm
Warranty & Support
Koolux e-bike frames, front fork components, handlebars, folding tubes and saddle tubes are covered by a 1-year warranty. This warranty includes replacements only. Labour charges are not included, and any labour must be performed by an authorised Koolux distributor.
Koolux batteries and associated parts have a 6-month warranty. covering faults such as poor contact, power failure, no power storage, or capacity below 60%.
Original Koolux parts & components are covered by a warranty of 1-8 months, depending on the part (see breakdown below). When spare parts are sent to the customer under warranty, the customer is liable for any freight costs.
At a glance
• Warranty cover included
• UK-based support
• Help with parts, guidance and next steps
🛠️
Warranty cover
Frame, front fork components, handlebars, folding tubes and saddle tubes: 1 year
What’s covered:
Chilled Rides will replace any component that is deemed to be defective or damaged, and not as a result of user error, including damage incurred during shipment.
💬
How support works
Support:
Handled via our UK support team in partnership with the manufacturer.
If you need support, contact us with your order number and details of the issue. We’ll review the problem and guide you through the next steps. Proof of purchase and photos or videos of the damaged product are required with any warranty request.
Repair method:
Coordinated from the UK by our support team.
Where possible, issues are resolved through troubleshooting or replacement parts before recommending more involved repairs.
⚠️
What’s not covered
Warranty does not cover normal wear and tear, accidental damage, misuse, or unauthorised modifications. Common wear items such as brake pads, tyres and chains are not typically covered, as expected with regular use.
For full details, please refer to the manufacturer’s warranty terms.
View full terms & exclusions
Warranty cover does not include wear and tear, accidental damage, misuse, neglect, water ingress, parts compromised due to corrosion due to the elements (moisture, heat, etc), or issues resulting from unauthorised modification.
Defects or damage resulting from any of the following are not covered by warranty:
Users disassembling, repairing or modifying the bike themselves, and any failures caused by non-compliance with the rules of use.
Failure caused by user accident, or improper use or storage by the user.
The cost of going to other repair shops for repairs without consent.
Slight scratches or damage to outer packaging caused by the logistics company during shipping of the accessories.
Additionally, any defects or damage caused by improper assembly, testing, operation, maintenance, installation, service, repair or adjustment, in a manner that varies from the instruction manual, are not covered.
Please contact us and obtain our written approval before sending any item back. Any products returned without acceptance will not be refunded.
🔧
Assembly, servicing & aftercare
If your bike arrives boxed or partially assembled, any remaining
assembly, adjustment and safety checks need to be completed correctly
before you ride it. Please follow the manufacturer's instructions
supplied with your bike.
If you're not confident carrying out the setup or checks yourself,
we strongly recommend using a competent bicycle mechanic or suitably
trained cycle professional.
You're responsible for making sure the bike is correctly assembled
and safe to ride before first use, as well as for routine servicing,
adjustment and maintenance. Problems caused or contributed to by
incorrect assembly, setup, misuse, wear or inadequate maintenance
may not be covered as product faults.
This does not affect your statutory rights in relation to genuinely
faulty goods.
Bikes are usually delivered to most UK mainland addresses within 3–7 working days of order placement. Northern Ireland, Northern Scotland and the Channel Islands may take longer and may incur additional shipping fees.
Bikes are delivered boxed and around 80% assembled. Some final assembly, adjustment and safety checks will therefore be needed before your first ride. Depending on the model, this may include fitting or checking the handlebars, stem, pedals or wheels, checking tyre seating and pressures, adjusting brakes and gears, and checking spokes, fasteners and other safety-critical components.
Please follow the manufacturer's instructions supplied with your bike and make sure everything is correctly assembled, adjusted and secure before riding. If you're not confident carrying out the setup or checks yourself, we recommend asking a competent bicycle mechanic or suitably trained cycle professional to help.
Orders are processed within 1–2 working days before dispatch. Delivery times may be slightly longer for made-to-order, fully built or other specialist delivery options.
Returns & Refunds
We offer 28-day returns, subject to our returns policy. If you wish to return your bike, please contact us first so we can explain the process and any applicable return transport arrangements.
If an item is faulty, damaged or incorrect, your statutory consumer rights remain unaffected.