Koolux BK6S 4.0 Folding Electric Bike
SKU: B94949In Stock
SPEED15.5 Mph
RANGE28 Miles
MOTOR250W
BATTERY13Ah
CHARGING6-7 Hours
WEIGHT73 lbs
This Model Is Fully Compliant With UK Road Regulations
This bike is built to comply with UK Electrically Assisted Pedal Cycle (EAPC) regulations, meaning it can be used on public roads and cycle paths without registration, tax, or a licence. Motor assistance is limited to 250W and cuts off at 15.5 mph (25 km/h).
See UK LegislationYour all-terrain folding companion
The Koolux BK6S 4.0 is built for UK riders who want one bike for the daily commute and weekend escapes. Whether you are weaving through city traffic or exploring gravel paths in the Peaks, this folding e-bike delivers reliable power, stable fat tyres, and a compact fold that fits into a car boot or under a desk. With a 250W motor, 28 miles of range, and a top assisted speed of 15.5 mph, it is fully compliant with UK road law and ready for real British weather.
Quiet, legal power for every hill
The 250W rear hub motor gives you smooth, responsive assistance up to 15.5 mph, exactly within UK regulations. Paired with a Shimano 7-speed gear set, it makes light work of steep city climbs and rolling countryside lanes. You stay in control, with power that feels natural and never jerky.
Long-range battery for real journeys
The 48V 13Ah lithium-ion battery delivers up to 28 miles on a single charge, enough for most UK commutes and leisure rides. It is removable, so you can charge it indoors at home or the office. A full charge takes 6-7 hours, and the battery is IP54 rated to shrug off rain and puddle splashes.
Fat tyres and suspension for comfort
20×4.0 inch fat tyres and a front fork suspension soak up potholes, kerbs, and rough towpaths. You get a planted, confident ride even on loose gravel or wet leaves. The wide contact patch improves grip and stability, so you can tackle mixed terrain without rattling your bones.
Confident stopping in all conditions
Mechanical disc brakes give you reliable, easy-to-modulate stopping power in rain or shine. The integrated rear safety light and StVZO-certified front headlight keep you visible on dark UK mornings and evenings. Full-coverage mudguards stop spray from soaking your clothes.
Clear display and practical controls
The multifunctional LCD display shows your speed, battery level, and assist mode at a glance. Controls are simple and within thumb’s reach, so you can adjust assistance without taking your eyes off the road. It is designed for real-world riding, not fiddly menus.
Strong frame, easy fold, everyday ready
The aluminium alloy frame keeps the bike light enough to carry up stairs yet strong enough for a 265 lb load. It folds down in seconds for storage in a hallway, car boot, or train luggage rack. A sturdy rear rack and full fenders mean you can carry shopping or a change of clothes without fuss.
- BRAND
- KOOLUX
- CATEGORY
- Folding
- MOTOR POWER
- 250W
- RANGE
- 28 Miles
- SPEED
- 15.5 Mph
- BATTERY
- 13Ah
- WEIGHT
- 73 lbs
- CHARGING TIME
- 6-7 Hours
- BRAKE SYSTEM
- Mechanical Brakes
- FRAME MATERIAL
- Aluminum Alloy
- MAXIMUM LOAD
- 265 lbs
- INPUT VOLTAGE
- 48V
- TIRE SIZE
- 20 inch
- TORQUE
- N/A
Secure checkout and fast UK delivery on every order.
- Free standard UK delivery on most bikes — 2 to 7 business days
- Express delivery may be available on request
- Full tracking included with every order
- Pay securely with Visa, Mastercard, PayPal, Apple Pay, Google Pay, or Klarna
- 0% finance available through Klarna at checkout
Before you order:
- Delivery is to UK mainland addresses — some remote areas may have a small surcharge
- Most bikes arrive 85–90% pre-assembled and include basic tools for setup
- If you are unsure about sizing or specs, contact us before you buy
Full details at Payment & Shipping.
Simple and fair terms so you can buy with confidence.
- 14-day return window — if the bike is not right for you, send it back
- The bike must be unused, in original packaging, with all accessories included
- A refund or replacement is issued after we receive and check the return
Please note:
- Returns for change of mind must meet the unused and original condition requirement
- If we sent the wrong item or it arrived faulty, we cover return shipping in full
- All bikes include a 12-month manufacturer warranty as standard
Full details at Returns & Refunds and Warranty.
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