isinwheel U4 Foldable Step-Thru Electric Bike
SKU: H54614In Stock
SPEED19 Mph
RANGE55 Miles
MOTOR250W
BATTERY10.4Ah
CHARGING4-5 Hours
WEIGHT58 lbs
Adjustable Cycle Helmet£38.99
Front and Rear Light Set£44.99
Private Land Use Only.
Not for public roads, pavements or cycle paths. Its motor and assisted top speed are above the UK EAPC limits of 250W and 15.5 mph, which makes it a motor vehicle in law. It would need registration, insurance and a licence. Ride it on private land.
See UK LegislationThis bike is built for riders 4'7"-5'11" (140-180 cm).
Kept in this browser only.
The manufacturer's figures, not ours.
This one carries 374 Wh of battery. The maker quotes 55 mi; in mixed riding with some hills, expect nearer 41 mi. A full charge costs about £0.10. Across a year that is roughly £986.00 less than making the same journeys by car, so the bike pays for itself in about 7 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 | 55 mi |
|---|---|
| Mixed riding, some hills | 41 mi |
| Full assist, loaded or hilly | 30 mi |
| Riding time on a charge | 2 h 53 min |
What it costs to run
| A full charge | £0.10 |
|---|---|
| Every 100 miles | £0.19 |
| Electricity for a year | £4.00 |
| The same year by car | £990.00 |
| You keep | £986.00 |
| Pays for itself in | 7 months |
Worked out from the specification
| Battery energy | 374 Wh |
|---|---|
| Energy per mile | 6.8 Wh |
| Charger output | 2.6 A |
| Power to weight | 9.5 W/kg |
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.
Fifty five miles from a 375 watt hour pack
The isinwheel U4 is a folding step-through bike claiming 55 miles from a small 10.4 amp hour battery, at £564.
It can be unlocked to 19 mph, which is above the UK assistance limit, so we sell it for private use on private land. Please read the panel above before you order.
Why this one carries the restricted notice
The motor is 250W, which is within the rules. The speed is not: isinwheel publish a default of 25 km/h and an unlocking speed of 30 km/h, which is 19 mph.
A bike that can be set above 15.5 mph of assistance is outside the definition of an electrically assisted pedal cycle in the UK, so we sell it for use on your own property or on land where the owner has given you permission. We flag it on the specification rather than on what the box says when it arrives.
Step-through and folding together
You step through instead of swinging a leg over, and it folds to 32.3 by 20.9 by 26.8 inches.
- Easy on and off with a bag on the rack
- A foot down without dismounting
- Folds into a car boot or a hallway cupboard
- Fifty eight pounds, so you wheel it rather than carry it far
Fifty five miles is a lot to ask of ten amp hours
Three hundred and seventy five watt hours is a small pack, and 88 km is a long claim against it. That figure is measured at the lowest assist level on flat ground.
The arithmetic works because the bike is small: sixteen inch wheels on 2.15 inch tyres, moving fifty eight pounds. It is not carrying its own weight before it carries yours the way a fat bike is.
The panel below turns the capacity into energy per mile and gives you the honest bands. Plan around the mixed one.
Zero-start, and what it is for
Zero-start means the motor will move the bike from a standstill rather than waiting for you to get the pedals turning first.
On a step-through frame with a low saddle that is genuinely useful: pulling away on a slope, or moving off with a load, without needing a push to begin with.
The battery comes out
Detachable, so it charges on a kitchen worktop rather than requiring the bike to be parked next to a socket. Four to five hours to full.
isinwheel list temperature, overload and water protection on the pack, which is the set of protections a battery management system should have and not every maker at this price names.
Lights, a screen and a twenty per cent gradient
An adjustable headlight, a handlebar reflector and a tail light, with a large LCD screen. IPX4, which is splash resistant.
The climbing figure is twenty per cent, a one in five slope, which is steep for a 250W motor with a 500W peak and a good deal steeper than most manufacturers will commit to in writing.
Who it fits
isinwheel size it for riders between 140 cm and 180 cm, which is 4ft 7in to 5ft 11in, and recommend it from fourteen years old.
The saddle runs from 29.1 to 36.2 inches and the bar sits at 40.6 inches. That is a small bike, and the fit range is the honest constraint on it: over about 5ft 11in, look at something with larger wheels.
Before the first ride
It arrives with the charger, the pedals, a tool kit and a manual.
- Unfold and lock the frame hinge and the stem, then check both are tight
- Fit the pedals and set the saddle inside the 29.1 to 36.2 inch range
- Check tyre pressure on both sixteen inch wheels
- Check the brakes before you use the assistance
- Charge to full before the first ride
Two figures isinwheel did not publish
There is no brake type and no maximum load for this model, so the table below leaves both rows out rather than inventing them.
The load rating is the one that matters, and we would rather say we do not have it than print a number. Ask us before you order and we will chase the supplier.
Buy this if you are inside the height range, you want something genuinely small and light that steps through and folds, and you have somewhere to ride it. At £564 with a 375 watt hour pack and zero-start, it is a lot of bike for the money.
- BRAND
- isinwheel
- CATEGORY
- Folding
- MOTOR POWER
- 250W
- RANGE
- 55 Miles
- SPEED
- 19 Mph
- BATTERY
- 10.4Ah
- WEIGHT
- 58 lbs
- CHARGING TIME
- 4-5 Hours
- BRAKE SYSTEM
- N/A
- FRAME MATERIAL
- Aluminum Alloy
- MAXIMUM LOAD
- N/A
- INPUT VOLTAGE
- 36V
- TIRE SIZE
- 16 inch
- TORQUE
- N/A
The isinwheel U4 Foldable Step-Thru Electric Bike states 250W, 55 Miles and 19 Mph, and below it is set against the DYU A1F Electric Folding Bike. Every figure the two disagree on is marked. Choose a different bike to compare it with whichever one you are also considering.
6 of 10 specifications differ. View DYU A1F Electric Folding Bike
- What is the maximum range of the iSinwheel U4?
- The U4 offers a maximum assisted riding range of up to 55 miles (55 miles) under ideal conditions. Actual range varies depending on terrain, rider weight, weather, and assist level.
- Is the battery removable?
- Yes. The 36V 10.4Ah lithium battery is removable, allowing convenient charging either on or off the bike.
- Can the iSinwheel U4 be folded for transport?
- Yes. The U4 features a quick-folding frame, making it easy to store in small spaces or transport in a car boot.
- Is the iSinwheel U4 suitable for commuting?
- Yes. Its compact size, step-through frame, long battery range, foldable design, and comfortable riding position make it an excellent choice for daily commuting and city riding.
- 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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