SUNNIGOO B5 Fat Tyre Electric Bike – 250W, 48V 12.5Ah (600Wh), 20x4.0 Tyres, Hydraulic Disc Brakes

A 250W fat-tyre e-bike that carries your week — and keeps to 25 km/h

The SUNNIGOO B5 pairs a 20x4.0 fat tyre chassis with a 48V 600Wh battery and hydraulic disc brakes. It is built for riders who need grip on broken asphalt, gravel and wet cobbles, plus real carrying capacity: a front basket, an aluminium rear rack rated to 15 kg and full-length mudguards come fitted. The motor is rated at 250 W continuous and assistance stops at 25 km/h, so it stays an ordinary bicycle in the eyes of the law.

Everything is powered by one removable 48V 12.5Ah (600Wh) pack — 50 to 80 km of assisted riding per charge, about 6 hours to refill, and a key lock so you can take it indoors to charge.

Why Riders Choose the SUNNIGOO B5

What you get	What it means for you
48V 250W rear hub motor	Rated at the 250 W continuous ceiling, so it pulls away cleanly on a slope and holds 25 km/h into a headwind — and stays a legal bicycle everywhere in the EU.
48V 12.5Ah (600Wh), removable	About 50% more capacity than the 36V packs on comparably priced city e-bikes. Comes out with a key so you can charge it indoors.
20 x 4.0 inch Chaoyang fat tyres	A wide contact patch that rolls over gravel, wet cobbles, sand, kerbs and tram tracks instead of catching in them — the reason riders buy a fat-tyre bike in the first place.
Hydraulic disc brakes, front and rear	Fingertip stopping power in the wet, with far less lever effort than mechanical discs. A 33 kg bike plus luggage needs brakes you can trust at the bottom of a hill.
Shimano 7-speed gearing	You pick the cadence and the motor handles the load. Ride past the 25 km/h cut-off on the flat using almost no battery.
Carries real loads — basket, rack, mudguards	Front basket, an aluminium rear rack rated to 15 kg and full-length mudguards are fitted as standard: grocery runs, a delivery shift or a pannier of work kit.
Suspension fork plus fat tyres	Two layers of comfort working together — the fork takes the pothole, the tyre takes the broken asphalt, and your back barely notices either.
EN 15194 pedal assist	No licence, no insurance, no registration — legally a bicycle across the EU, the UK and Switzerland.

SUNNIGOO B5 Full Specifications

Brand	SUNNIGOO
Model	B5
Colour	Cream White (in stock) or Military Green (on request)
Motor	48V 250W rear hub motor
Battery	48V 12.5Ah (600Wh) lithium-ion, removable with key lock
Charger	54.6V 2.0A, 100-240V, European standard round plug
Charging time	Approx. 6 hours
Display	LCD display with PAS indicator, battery level and light control
Assist type	Pedal assist (PAS) – the motor runs only while you pedal
Top assist speed	25 km/h (EU / UK legal pedal-assist cut-off)
Assist range	50–80 km depending on load, terrain and assist level
Frame	6061 aluminium alloy
Fork	Suspension fork
Gears	Shimano 7-speed with rear derailleur
Brakes	Front and rear hydraulic disc brakes
Tyres	20 x 4.0 inch Chaoyang fat tyres
Rear rack	Aluminium, max load 15 kg
Front basket	Fitted as standard
Mudguards	Aluminium, front and rear
Lights	Front LED (48V DC); rear LED with integrated battery
Saddle	Soft city saddle
Kickstand	Fitted as standard
Max load	100 kg
Net weight	33 kg with battery / 29.5 kg without
Gross weight	40 kg
Package size	147 x 28 x 79 cm
Assembly	85% pre-assembled – front wheel, pedals, seat and handlebar to fit
Folding	No

Is the B5 Legal to Ride in Europe?

Yes. The B5 is built as an EPAC (Electrically Power Assisted Cycle) under EN 15194. That means:

• Motor rated 250 W continuous — the ceiling for a pedal-assist bicycle in the EU and the UK.
• Assistance cuts off at 25 km/h, and the motor only runs while you are pedalling.
• No throttle, so no moped classification: no licence, no insurance, no number plate.
• Ride it on cycle paths, in bus lanes and on the road exactly like an ordinary bicycle.

Note: national rules vary in detail (for example, some countries require a bell or reflectors, and Germany treats EPACs as bicycles under the eKFV). Always check your local traffic code before riding.

What’s in the Box

• SUNNIGOO B5 e-bike (85% pre-assembled)
• 48V 12.5Ah battery pack with 2 keys
• 54.6V 2.0A charger (European round plug)
• Front basket and aluminium rear rack (fitted)
• Front and rear mudguards, front and rear LED lights (fitted)
• Hex key set and wrenches
• Pedals (marked L / R)
• User manual

The bike arrives 85% assembled — fit the front wheel, pedals, saddle and handlebar, charge the battery and you are riding. Most riders are done in 20 to 30 minutes.

Built and Supported by SUNNIGOO

The B5 is sold under the SUNNIGOO brand. Every bike is inspected before it leaves the factory, ships from our EU warehouse with local delivery and local returns, and is backed by our own support team for setup questions, tuning and spare parts — you deal with us, not with a marketplace seller.

Frequently Asked Questions

How far can the B5 go on one charge?

Around 50–80 km of assisted riding, depending on your weight, how much you carry, the terrain and the assist level. Flat routes at the lowest level sit at the top of that range; hilly rides with a loaded rack sit at the bottom.

Does it have a throttle?

No. The B5 is pedal-assist only — the motor adds power while you pedal and stops helping at 25 km/h. That is what keeps it a legal bicycle in Europe rather than a moped.

Why fat tyres instead of normal ones?

A 4.0-inch tyre runs at low pressure and puts a much wider patch of rubber on the road, so it grips on wet cobbles, gravel, sand and broken asphalt, and it soaks up kerbs and potholes that would jar a narrow-wheeled bike.

Is the battery removable, and how long does it take to charge?

Yes — the 48V 12.5Ah pack unlocks with a key and slides out, so you can charge it indoors. A full charge from empty takes about 6 hours with the supplied 54.6V 2.0A charger.

How much can it carry?

Total load capacity is 100 kg including the rider, and the aluminium rear rack is rated to 15 kg. The front basket, rear rack and mudguards are all fitted as standard.

What colours are available?

Two: Cream White — the off-white bike shown in the photos — and Military Green. Cream White is stocked in our EU warehouse and ships first, and it is the colour shown throughout this page. Military Green is built to order: select it at checkout, or message us before ordering and we will confirm the lead time. Both colours ship with the same motor, battery, rack, basket and mudguards; only the paint differs.

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SUNNIGOO B5 — fat tyre electric bike for adults. 48V 250W rear hub motor, removable 48V 12.5Ah (600Wh) battery, Shimano 7-speed, 20x4.0 Chaoyang fat tyres, suspension fork and hydraulic disc brakes. EN 15194 pedal assist, 25 km/h cut-off. Shipped from our EU warehouse with fast local delivery and local returns.