isinwheel U4 Foldable Step-thru Electric Bike
SKU: H54614In Stock
SPEED19 Mph
RANGE55 Miles
MOTOR250W
BATTERY10.4Ah
CHARGING4-5 Hours
WEIGHT58 lbs
This Bike Is Not Road Legal. Private Land Use Only.
This bike cannot be ridden on public roads, pavements, or cycle paths in the UK. Its motor output and assisted top speed exceed the legal limits set by the UK Electrically Assisted Pedal Cycle (EAPC) regulations, which cap electric bikes at 250W motor power and 15.5 mph (25 km/h). Because this bike exceeds both thresholds, it is classified as a motor vehicle and would require registration, insurance, and a valid licence to use on public roads. This bike is designed exclusively for use on private land such as farms, estates, and off-road tracks where road traffic law does not apply.
See UK LegislationYour everyday ride, simplified
The isinwheel U4 is for anyone who wants a practical, no-fuss way to get around town. Whether you're commuting to work, popping to the shops, or just enjoying a weekend ride, this foldable step-thru e-bike makes every trip easier. With a 250W motor, up to 55 miles of range, and a top assisted speed of 19 mph, it's built for real UK streets and everyday life.
Power that keeps up with you
The 250W motor delivers smooth, reliable assistance for city riding, with a peak output of 500W for confident acceleration. It helps you tackle hills up to a 20% gradient without breaking a sweat. And because it's fully UK road legal, you can ride it anywhere a normal bike is allowed.
Go further on a single charge
The removable 36V 10.4Ah battery gives you up to 55 miles of assisted range, so you can cover your weekly commute or a long leisure ride without range anxiety. Charging takes just 4–5 hours, and because the battery is detachable, you can charge it indoors or at your desk. The battery also features temperature, overload, and waterproof protection for peace of mind.
Comfort that makes you want to ride
The step-thru aluminium frame makes mounting and dismounting effortless, even if you're wearing a coat or carrying a bag. The saddle is designed for comfort on real streets, and the adjustable seat height (29.1"–36.2") suits riders from 4'7" to 5'11". With 16" tyres and a smooth ride, you'll look forward to every journey.
Stay safe and seen
The U4 comes with an adjustable headlight, a handlebar reflector, and a tail light, so you're visible on early-morning commutes or evening rides. The IPX4 waterproof rating means light rain won't stop you, and the reliable braking system helps you stop confidently in traffic. Ride with peace of mind, whatever the British weather throws at you.
Clear controls, simple riding
The large LCD screen shows your speed, battery level, and assist mode at a glance, so you can focus on the road. Choose from multiple assist levels to match your effort, or use the zero-start feature to pull away smoothly from a standstill. Everything is designed to be intuitive, even if you're new to e-bikes.
Built to fold, made to last
The U4 folds in seconds to just 32.3" × 20.9" × 26.8", so it fits in a car boot, under a desk, or in a hallway cupboard. The aluminium alloy frame is lightweight yet sturdy, supporting a total weight of 58 lbs. When unfolded, it's a full-size ride at 56.3" long, giving you stability and comfort on every trip.
- BRANDisinwheel
- CATEGORYFolding
- MOTOR POWER250W
- RANGE55 Miles
- SPEED19 Mph
- BATTERY10.4Ah
- WEIGHT58 lbs
- CHARGING TIME4-5 Hours
- BRAKE SYSTEMN/A
- FRAME MATERIALAluminum Alloy
- MAXIMUM LOADN/A
- INPUT VOLTAGE36V
- TIRE SIZE16 inch
- TORQUEN/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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