Does the Koolux BK6S 4.0 Electric Bike fold for storage?

Yes. The frame and stem fold to approximately 96 × 38 × 75 cm. That helps with boot or shed space, but it remains a substantial 20-inch fat-tyre bike, so check the vehicle opening and lifting height before relying on the fold.

Can the Koolux BK6S 4.0 battery be removed for indoor charging?

Yes. The lockable battery can be charged on the bike or removed and taken indoors. Support it securely as it slides out, use the supplied charger on a dry, stable surface and make sure it clicks and locks fully back into position before riding.

How does the Koolux BK6S 4.0 differ from the BK6S Pro?

The standard BK6S 4.0 uses one battery and is the simpler choice for typical rides. The BK6S Pro carries two batteries with 23.4Ah combined capacity, giving it a longer-distance focus but adding cost and weight.

Will the Koolux BK6S 4.0 fit a shorter or taller rider?

Published guidance places it around 165–195 cm, but height alone does not guarantee comfort. Its 20 × 4-inch tyres and folding frame still create a fairly tall, broad bike. Check that you can stand over the frame, reach both brake levers and achieve a safe knee bend at the lowest suitable saddle position.

Is the Koolux BK6S 4.0 Electric Bike easy to assemble?

The Koolux BK6S 4.0 Electric Bike arrives mostly assembled. Final setup normally includes aligning and securing the handlebars, fitting the pedals and completing essential safety checks. Allow approximately 20–30 minutes, or select our professional assembly and PDI service.

Is the Koolux BK6S 4.0 Electric Bike water resistant?

The Koolux BK6S 4.0 Electric Bike is not fully waterproof. Avoid prolonged exposure to heavy rain, and never submerge or pressure wash the bike or its electrical components. After riding in wet conditions, wipe the bike dry and store it in a dry, sheltered location.

Koolux BK6S 4.0 Electric Bike 500W 48V 15Ah

Certified

Koolux BK6S 4.0 Electric Bike

SKU: TS-10181-BLUETURQUO

Motor

500W

Battery

48V 15AH

Speed

15.5 MPH

Range

41 MILES

£899.00 £659.99

In stock 17 sold this week

Klarna £220.00 ×3

Clearpay £165.00 ×4

PayPal £220.00 ×3

Finance

From —/mo 24, 36 or 48 months at 15.9% APR 6 or 12 months at 0% interest

Shop Pay

From £55.00/mo 12 months at 0% interest Up to 24 months available

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Standard Home Delivery 3–5 working days

Our standard tracked home delivery service for most UK mainland orders.

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Available at checkout on selected in-stock items only. If Next Day Delivery is available for your order, it will appear before payment.

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Click & Collect Collection from our Nuneaton workshop

Collect from our Nuneaton workshop

Collection is available by appointment from our Nuneaton workshop. The preparation time depends on where the product is currently stored. Contact us before ordering for the latest availability, or place your order and we will confirm when it is ready to collect.

Transfer required to Nuneaton Usually 5–7 working days

Products stored at another warehouse normally require 5–7 working days to reach our workshop. We will confirm as soon as the item is ready and arrange your collection appointment.

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Marketplace or private sellers, used or clearance items, private codes, finance-only offers, bundle deals and obvious errors are excluded

Usually answered within 24 hours. Need a quicker answer? WhatsApp us or call 0800 099 6187.

Why Buy From TrailSurge? UK showroom, product support & aftercare

Buy your Koolux BK6S 4.0 Electric Bike with UK-based support

TrailSurge is a UK retailer with a showroom and workshop in Nuneaton. Our team can help before you order and continue supporting you after your Koolux BK6S 4.0 Electric Bike arrives.

UK-based customer support before and after your purchase
Showroom and workshop in Nuneaton
Help with product questions, setup, parts and aftercare
Tracked UK delivery with support if you need help with your order
Speak to a real member of our team before placing your order

Why buy through TrailSurge? For the best UK-based support and aftercare, we recommend buying through TrailSurge rather than ordering directly from overseas manufacturers or China-based sellers, where returns, warranty support and parts handling can be more difficult.

Need help with the Koolux BK6S 4.0 Electric Bike? Ask our team a question before ordering.

WhatsApp Us Call Us 0800 099 6187

Road use notice: This bike is over 250W and is for private land/off-road use only. Need a UK road-compliant option? View road legal e-bikes .

Check your fit

Size & Rider Fit

Maximum Rider Weight: 150KG

Trail Surge Warranty Plus FULL OFFICIAL WARRANTY INCLUDED UK-based support alongside the manufacturer warranty TRAILSURGE COVER 12 months

TWO LAYERS OF PROTECTION

More confidence after you buy

TrailSurge Warranty+ gives you a direct UK warranty alongside the product’s manufacturer warranty.

01 TRAILSURGE WARRANTY +

12 months of TrailSurge support

UK-based fault support
Battery, motor and frame fully covered.
Repair, parts or another suitable solution where eligible

02 Koolux WARRANTY

Manufacturer warranty period 12 months against manufacturing defects.

Manufacturer cover

Confirmed production faults affecting the original frame and factory-installed electrical or mechanical components.

Typical component protection Eligible faults affecting the frame and forks, motor and drive system, controller, battery and BMS, charger, wiring, display, gears, brakes and factory-fitted controls.

Description

Quick Summary
The KOOLUX BK6S 4.0 combines rugged fat‑tyre traction with a powerful 750W motor and a high‑capacity 48 V 13 Ah battery. Designed for both urban streets and off‑road paths, it delivers stable handling and dependable performance.

Smooth Power Delivery
The 750W hub motor offers responsive acceleration and smooth pedal‑assist across seven levels, letting you tackle hills and headwinds without strain. A thumb throttle provides instant power when you need a boost.

Comfort & Control
Wide 4.0″ tyres and front suspension absorb bumps and maintain grip on loose or uneven surfaces. Dual mechanical disc brakes ensure consistent, controlled stopping power in all weather.

Smart Battery System
A lockable, removable 48 V 15 Ah battery provides long-range capability and convenient off‑bike charging. Built‑in protection circuits guard against over‑charge, over‑discharge, and overheating for safe, reliable use.

Tech You Can Trust
The clear backlit LCD displays speed, battery level, distance travelled, and assist mode at a glance. Simple handlebar controls let you switch assist levels and monitor ride data easily.

Built for Everyday Use
With its durable frame, fat‑tyre stability, and straightforward folding rack mount design, the BK6S 4.0 is ready for daily commutes, weekend adventures, and everything in between—wherever you choose to ride.

Specifications

Collection	Koolux Electric Bikes
Brand	Koolux
Bike Type	City & Commuter, Folding, Fat Tyre
Motor Power	500W
Battery	48V 15AH
Top Speed	15.5 MPH
Max Range	41 Miles
Charging Time	5+ Hours

Shock Absorbers	Front
Brakes	Dual Mechanical Disc Brakes
Bike Weight	27KG
Max Climb	15 degrees
Max Rider Weight	150KG
Dimensions
Built Dimensions	182 × 60 × 110 cm (L × W × H)
Box Dimensions	93 × 55 × 76 cm (L × W × H)

A labeled diagram of an electric bicycle highlights its parts, including the dashboard, handle bar, saddle, battery pack, motor, disc brake, pedals, front light, fender, and quick release locks.

Close-up of an e-bike’s handlebar and display, highlighting buttons and controls for battery status, real-time speed, and driving distance. The image also shows the Shimano seven-speed gear and three riding modes: pure electric, moped, and normal.

What’s Included in the Box?

1 x Koolux BK6S 4.0 Electric Bike

1 x Charger

2 x Keys

1 x Tool Kit

1 x User Manual

Frequently Asked Questions

A REAL SHOWROOM. A REAL TEAM.

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We have a real showroom and workshop in Nuneaton. See a selection of electric bikes, scooters and dirt bikes, speak to our team, and buy with confidence knowing who is here to help.

Explore the showroom Call 0800 099 6187

Appointment only. Please confirm the model you want to see before travelling.

TrailSurge showroom and workshop in Nuneaton

Real UK showroom

Visit us in NuneatonUnit 62, Centenary Business Centre, CV11 6RY

Koolux BK6S 4.0 Electric Bike

Size & Rider Fit

More confidence after you buy

Description

Specifications

Dimensions

What’s Included in the Box?

Frequently Asked Questions

Does the Koolux BK6S 4.0 Electric Bike fold for storage?

Can the Koolux BK6S 4.0 battery be removed for indoor charging?

How does the Koolux BK6S 4.0 differ from the BK6S Pro?

Will the Koolux BK6S 4.0 fit a shorter or taller rider?

Is the Koolux BK6S 4.0 Electric Bike easy to assemble?

Is the Koolux BK6S 4.0 Electric Bike water resistant?

Customer Reviews

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