Koolux BK6S PRO Folding Electric Bike
SKU: I49880
SPEED15.5 Mph
RANGE50 Miles
MOTOR250W
BATTERY13+10.4Ah
CHARGING5 Hours
WEIGHT87 lbs
Adjustable Cycle Helmet£38.99
Front and Rear Light Set£44.99
In stock now, a similar model
Samebike LO26-II-YD Folding Electric Mountain Bike£689.00In stockView
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 LegislationThis one carries 624 Wh of battery. The maker quotes 50 mi; in mixed riding with some hills, expect nearer 38 mi. A full charge costs about £0.17. Across a year that is roughly £982.00 less than making the same journeys by car, so the bike pays for itself in about 13 months. Everything here is worked out from this bike's own specification. Estimates, not promises: the assumptions are printed underneath.
Range you can expect
| Low assist, flat roads | 50 mi |
|---|---|
| Mixed riding, some hills | 38 mi |
| Full assist, loaded or hilly | 28 mi |
| Riding time on a charge | 3 h 14 min |
What it costs to run
| A full charge | £0.17 |
|---|---|
| Every 100 miles | £0.35 |
| Electricity for a year | £8.00 |
| The same year by car | £990.00 |
| You keep | £982.00 |
| Pays for itself in | 13 months |
Worked out from the specification
| Battery energy | 624 Wh |
|---|---|
| Energy per mile | 12.5 Wh |
| Charger output | 2.6 A |
| Power to weight | 6.3 W/kg |
| You can carry | 265 lb |
Based on £0.245 per kWh, £0.45 per mile to run a small car, and 2,200 miles a year. Charging is costed at the socket, not at the battery.
Two batteries, and KOOLUX charges them differently
The KOOLUX BK6S PRO carries two batteries, 13Ah and 10.4Ah, on a folding frame, at £989.
250W and 15.5 mph: it meets the EAPC rules, so there is no licence, no tax and no registration.
A frame battery and a rack battery, with their own charging times
KOOLUX publishes them separately, which is unusual and useful.
- Frame battery: five to six hours
- Rack battery: six to seven hours
- Twenty-three amp hours between them at 48V
- Eighty to a hundred and fifty kilometres claimed
Two packs also mean a failure in one does not leave you walking, and you can charge only one when the ride is short.
Fifty miles in our table, against 150 km claimed
Our table carries the cautious figure rather than the top of KOOLUX's range.
One hundred and fifty kilometres assumes flat ground, the lowest assist level and real pedalling on an 87 lb bike. The panel below turns the capacity into energy per mile so you can see the arithmetic rather than take the headline on trust.
The brakes are mechanical, and at this weight you should know
Cable rather than hydraulic, on a bike weighing 87 lbs.
They stop well and want the cable tension checking now and then, but on a machine this heavy hydraulic would be better. It is the line that gives us most pause on this sheet, and the X11 above it in the range has hydraulic brakes for eighty pounds less.
An iron frame, and KOOLUX says so
Not aluminium: iron, at 39.3 kg.
Steel bends before it breaks, which matters at a folding hinge, and it damps vibration better than aluminium does. It also rusts, so keep it dry and watch for deep scratches. Most of the weight on this bike comes from the frame and the second battery together.
265 lbs of payload, and it is low for this machine
Lower than 96% of our catalogue: you and everything on the bike, together.
On an 87 lb bike that is the first line to check. Twenty by four inch fat tyres, a front suspension fork, Shimano 7-speed and an IP54 rating.
Before the first ride, and who it is for
KOOLUX publishes fourteen rows for this model. There is no torque figure and no rider height range, and both stay empty below rather than being invented.
- Unfold and lock the frame and the stem, then check both again after the first hour
- Bed both mechanical brakes in at walking pace and set the cable tension
- Check that tension again after the first ride
- Charge both batteries fully before the first long ride
- Run the tyres soft for grip, firmer for range
Buy it for the two batteries on a legal bike that folds. If you want the same range with hydraulic brakes, look at the X11 first.
- BRAND
- KOOLUX
- CATEGORY
- Folding
- MOTOR POWER
- 250W
- RANGE
- 50 Miles
- SPEED
- 15.5 Mph
- BATTERY
- 13+10.4Ah
- WEIGHT
- 87 lbs
- CHARGING TIME
- 5 Hours
- BRAKE SYSTEM
- Mechanical Brakes
- FRAME MATERIAL
- Iron
- MAXIMUM LOAD
- 265 lbs
- INPUT VOLTAGE
- 48V
- TIRE SIZE
- 20 inch
- TORQUE
- N/A
The Koolux BK6S PRO Folding Electric Bike states 250W, 50 Miles and 15.5 Mph, and below it is set against the DYU FF500 20 Inch Fat Tire Folding Electric Bike. Every figure the two disagree on is marked. Choose a different bike to compare it with whichever one you are also considering.
9 of 12 specifications differ. View DYU FF500 20 Inch Fat Tire Folding Electric Bike
- What is the benefit of the dual-battery system?
- The dual batteries provide longer riding range and consistent power for extended trips.
- Is it suitable for off-road riding?
- Yes, the fat tires and suspension system offer excellent traction and stability on rough terrain.
- Does it offer long-distance performance?
- Yes, it is designed for extended rides with a high-capacity battery setup.
- What are the benefits of the fat tires?
- Fat tires improve grip, comfort, and control on various road and trail conditions.
- Are the electric bikes brand new?
- Yes. All electric bikes sold by BikTron are brand new, factory-sealed, and sourced directly from authorised manufacturers and official distributors.
- How do I choose the right electric bike for me?
- Pick a bike based on how you plan to ride. City bikes are great for commuting, folding bikes work well if you need compact storage, mountain bikes handle hills and mixed terrain, and cargo bikes are ideal for carrying shopping or loads. If you are not sure, our Bike Quiz can help.
- Are the batteries original and certified?
- Yes. Every electric bike battery is brand new and original from the manufacturer, with full safety certification and performance testing.
- Are the bikes tested before shipping?
- Yes. Each e-bike goes through a quality check before dispatch, covering electronics, brakes, motor response, and battery performance.
- Do electric bikes come with a warranty?
- Yes. All electric bikes from BikTron include a manufacturer warranty. Duration depends on the brand and model. Most bikes include a 12-month warranty as standard.
- How long does delivery take?
- Standard UK delivery usually takes 2 to 7 business days. Remote areas may take a little longer. You will receive a tracking link by email once your order is dispatched.
- Which payment methods do you accept?
- We accept Visa, Mastercard, PayPal, Apple Pay, Google Pay, and Klarna buy-now-pay-later. All payments are processed securely.
- Can I return my electric bike?
- Yes. You can ride the bike and still return it. Tell us within 30 days of delivery and we book the courier and collect it from your door. Contact us first and we will guide you through the process.
- Do the bikes need assembly?
- Most electric bikes arrive 85 to 90 per cent pre-assembled. You will usually need to attach the handlebars, pedals, and adjust the seat. A basic tool set is often included.
- Are BikTron electric bikes legal to ride in the UK?
- Yes. All bikes sold by BikTron that meet UK EAPC rules (250W motor, max 15.5 mph assisted speed, pedal-assisted only) are fully road-legal. You do not need a licence, tax, or insurance to ride them on public roads. Riders must be at least 14 years old.
- What about the electric scooters?
- Those are different, and the law treats them differently. A privately owned e-scooter cannot legally be ridden on a public road, pavement or cycle lane in the UK, whoever sold it. We sell ours for private land use only, with the landowner's permission, and every scooter product page says so. If you want something you can ride to work, choose an electric bike.
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.
- 30-day return window — if the bike is not right for you, send it back
- Ride it. It needs to come back clean, undamaged and complete, with the charger, tools and manual
- A refund or replacement is issued after we receive and check the return
Please note:
- For a change of mind we book the collection and deduct its cost from your refund, and we tell you the amount before we book it
- 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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18+, UK residents. Credit subject to status. Terms apply.
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