If you are serious about range, two names keep coming up when shopping for a long range electric bike in the UK: the FREESKY Dual Battery fat tyre electric mountain bike and the Fafrees FF20 Polar Pro folding electric bike. Both use dual battery systems that genuinely double the distance of a standard single-battery rival, and both are sold through trusted UK retailers.
The catch is they are built for completely different riders. One is a full-suspension electric mountain bike made for rough trails and steep climbs. The other folds in seconds and fits in a car boot. Read on and we will tell you exactly which one deserves your money.
How We Compare
We evaluate electric bikes based on UK EAPC compliance, real-world battery efficiency, frame geometry for UK roads, build quality and long-term value for money. Specifications are cross-referenced against manufacturer listings and verified UK retailer data.
Brand Overview
About FREESKY
FREESKY builds high-performance fat tyre and dual motor electric bikes aimed at riders who want more from their machine. The brand is known for larger battery systems, aggressive braking hardware and all-terrain construction that goes further than most budget brands dare. Their Dual Battery model carries TUV UL2849 safety certification, which is an independent safety endorsement that is genuinely rare at this price point and worth paying attention to.
About Fafrees
Fafrees has earned a strong reputation in the UK electric bike market, particularly for long-range folding models and cargo trikes. The brand focuses on practical, everyday electric bikes that balance range, portability and value. The FF20 Polar Pro is their premium folding flagship model, designed for commuters and leisure riders who want serious distance without sacrificing the ability to store the bike in a flat hallway or take it on public transport.
Quick Verdict at a Glance
- FREESKY Dual Battery: Best for riders who want maximum range, heavy load capacity and serious off-road performance. The 41Ah dual battery, 4-piston hydraulic brakes and TUV certification make this the stronger technical choice. Not foldable.
- Fafrees FF20 Polar Pro: Best for commuters and leisure riders who need long range in a compact, foldable package. Faster charge time, lighter footprint and a folding frame make daily life considerably easier.
Specifications Compared
| Feature | FREESKY Dual Battery | Fafrees FF20 Polar Pro |
| Motor | 250W rear hub | 250W rear hub |
| Torque | Not stated | 65Nm |
| Battery | Dual 48V (18Ah + 23Ah = 41Ah) | Dual 48V (10.4Ah x2 = 20.8Ah) |
| Claimed Range | Up to 160 miles | Up to 160km |
| Real-World Range | 80 to 100 miles (mixed terrain) | 80 to 120km (mixed terrain) |
| Charge Time | 6 to 7 hours | 3 to 4 hours per battery |
| Brakes | 4-piston hydraulic disc | Dual 160mm disc |
| Suspension | Full dual | Front only |
| Tyres | 26×4.0 fat tyre | 20×4.0 fat tyre |
| Frame | Aluminium 6061 | Aluminium folding |
| Weight | Heavy (dual battery frame) | 34kg |
| Load Capacity | 400lbs (181kg) | 150kg |
| Safety Cert | TUV UL2849 | None stated |
| Folding | No | Yes |
| Colours | Classic Blue | Blue, Green |
| Price | £1,499 – £1,599 (GBP) | £699 – £899 (GBP) |
Battery and Range
Both are genuine dual battery electric bikes with two physically separate removable packs that combine for far greater range than anything a single-battery rival can offer.
The FREESKY Dual Battery pairs an 18Ah tube battery with a 23Ah frame battery, hitting a combined 41Ah total. A built-in battery equalisation system balances the load across both packs, reducing wear and extending overall lifespan, which is something many budget dual battery bikes skip entirely.
The Fafrees FF20 Polar Pro runs two 10.4Ah batteries for a combined 20.8Ah. Each battery charges fully in just 3 to 4 hours. If you commute daily and want to top up overnight without worrying about it, that faster turnaround often matters more than peak capacity.
- Real-World Range Note: The FREESKY’s 160-mile claim is based on ideal flat conditions at PAS level 1 with a light rider. On mixed UK terrain carrying gear, expect around 80 to 100 real-world miles. The Fafrees FF20 Polar Pro’s 160km claim similarly reflects optimal conditions. Most UK riders will see 80 to 120km in everyday use depending on hills, wind and assist level used.
Bottom line on range: the FREESKY wins outright on total capacity. The Fafrees wins on charging speed and daily convenience.
Motor and Performance
Both bikes run a 250W rear hub motor, keeping them fully within UK EAPC rules with no licence, no insurance and no road tax required on public roads. Neither uses a torque sensor, so assistance is cadence-based rather than pressure-sensitive.
Where they split is terrain capability. The FREESKY is built for hills and rough ground. The 6061 aluminium frame handles steep climbing angles and the 26×4.0 inch fat tyres grip mud, gravel, sand and rock with real confidence. As a fat tyre electric bike UK option for serious off-road use, it is hard to beat at this price.
The Fafrees FF20 Polar Pro handles gradients up to 25 degrees and performs well on roads, cycle paths and light trails. It was not designed for aggressive off-road riding and does not pretend to be. On tarmac and gentle countryside routes it is genuinely capable and comfortable.
Brakes and Safety
The gap here is significant and worth understanding before you buy.
When riding on damp UK tarmac, the difference in stopping confidence between these two bikes is immediately noticeable. The FREESKY’s 4-piston hydraulic brakes bite instantly with minimal lever pressure, giving you precise, progressive stopping power even on longer descents. The Fafrees requires a firmer pull on steep sections, which is perfectly manageable in everyday urban use but less reassuring on technical terrain.
Most electric bikes in this price range use 2-piston systems. Four pistons distribute clamping force more evenly across the rotor, which matters most on long descents and in wet conditions. The TUV UL2849 battery certification on the FREESKY adds another layer of verified safety that most brands at this price do not offer.
The Fafrees FF20 Polar Pro uses dual 160mm disc brakes front and rear, which are perfectly adequate for urban commuting and leisure riding.
FREESKY Dual Battery: Pros and Cons
- Pros:
- Massive 41Ah combined battery capacity for maximum range per charge
- TUV UL2849 certified battery system for verified safety
- 4-piston hydraulic disc brakes for confident stopping on steep terrain
- 400lbs (181kg) load capacity, one of the highest in this price range
- 26×4.0 inch fat tyres handle mud, sand, snow and gravel confidently
- Full dual suspension for rough trail comfort
- 6061 aluminium alloy frame built for durability
- Cons:
- Does not fold, requires garage or shed storage
- Heavy build due to dual battery system and full suspension
- Long 6-7 hour charge time for full capacity
- Additional performance modes are for private land only, not road legal in the UK
Fafrees FF20 Polar Pro: Pros and Cons
- Pros:
- Folds to 93x64x75cm in seconds with no tools required
- Step-through frame suits riders of all heights
- Fast 3 to 4 hour charge time per battery
- 20×4.0 inch fat tyres handle varied terrain
- 150kg load capacity suits most adult riders
- Available in blue and green
- Compact enough for car boots, offices and public transport
- Cons:
- Smaller 20.8Ah total battery capacity compared to FREESKY
- 2-piston disc brakes require firmer pull on steep descents
- 34kg total weight, heavy to carry upstairs
- Front suspension only, no rear shock absorber
Design and Practicality
This is where your lifestyle makes the decision more than any spec sheet.
The Fafrees FF20 Polar Pro folds to 93x64x75cm in seconds with no tools. It fits in a car boot, slides under a desk and goes on a train without any drama. The step-through frame makes mounting and dismounting easy for riders of all sizes.
The FREESKY Dual Battery does not fold. It is a full-size electric mountain bike that needs a garage, shed or dedicated storage space. You ride it from door to door. You do not carry it onto the Tube or lift it up three flights of stairs. If that suits your situation, great. If it does not, the FREESKY will quickly become an inconvenience regardless of how impressive the specs are.
UK Legal 250W Electric Bike Rules
Both bikes comply with UK EAPC (Electrically Assisted Pedal Cycle) regulations in their standard road modes. This means a 250W motor output, assistance cutting off at 25km/h and no throttle on public roads. Under these rules neither bike requires a licence, insurance or vehicle registration.
The FREESKY Dual Battery includes additional performance modes that are for private land use only. These are not permitted on UK public roads, cycle paths or pavements. Always check local regulations before using any non-standard riding mode.
Who Should Buy the FREESKY Dual Battery?
If you have storage space, ride challenging terrain regularly and want the absolute maximum range from a single charge, the FREESKY Dual Battery is the stronger technical package. The 41Ah dual battery system, 4-piston hydraulic brakes, 181kg load capacity and TUV certification combine to make a bike that is genuinely built to a higher standard than most rivals at this price.
It suits riders who head out for long countryside rides at weekends, tackle hills regularly or carry heavy loads and need a bike that will not let them down mid-route.
Who Should Buy the Fafrees FF20 Polar Pro?
If you commute by train, live in a flat or simply need a bike that fits into a normal daily routine without requiring a garage, the Fafrees FF20 Polar Pro is the more practical choice. The faster charge time, folding frame and manageable footprint make it far better suited to the way most UK riders actually use their electric bike.
It suits commuters, leisure riders and anyone who wants serious range without the bulk and storage demands of a full-size mountain bike.
Verdict
Bottom line? If you have space at home and want to tackle 100-plus mile off-road rides with serious braking hardware and the highest load capacity in this comparison, the FREESKY Dual Battery is worth every penny. But if you commute by train, live in a flat or need a bike that genuinely fits your daily life, the Fafrees FF20 Polar Pro is the smarter and more practical pick.
Both are among the best dual battery electric bikes available to UK buyers right now. Use our comparison tool to put any two bikes head to head and find the right match for your riding style.
Frequently Asked Questions
Is a dual battery electric bike worth buying in the UK?
For riders who regularly cover 50 miles or more per outing, a dual battery ebike makes a real difference. Both batteries on these bikes are removable and can be charged separately, giving you flexibility that a single-battery bike simply cannot match. For shorter daily commutes under 15 miles, the extra weight and cost of a dual system is probably more than you need.
Which bike has better range, the FREESKY Dual Battery or the Fafrees FF20 Polar Pro?
The FREESKY has more than double the raw battery capacity at 41Ah versus 20.8Ah. In real world UK conditions on mixed terrain, expect around 80 to 100 miles from the FREESKY and 80 to 120km from the Fafrees. The Fafrees compensates with a faster 3 to 4 hour charge per battery, making it easier to keep topped up between daily rides.
Do these bikes need a licence or insurance to ride in the UK?
No. Both bikes comply with UK EAPC rules in their standard modes with a 250W motor, assistance up to 25km/h and no throttle on public roads. That means no licence, no insurance and no road tax is required. The FREESKY includes additional modes for private land only, which must not be used on public roads.
Can both batteries be charged at the same time?
Both bikes have independent removable batteries, each requiring its own charger. To charge both at the same time you need two chargers. The Fafrees FF20 Polar Pro charges each battery in 3 to 4 hours, making simultaneous dual charging practical for most riders. The FREESKY takes 6 to 7 hours per charger, so a full dual charge takes considerably longer.
What is the maximum weight these bikes can carry?
The FREESKY Dual Battery supports up to 400lbs, which is approximately 181kg. That is one of the highest load limits of any electric bike at this price. The Fafrees FF20 Polar Pro supports up to 150kg. Both comfortably cover the vast majority of adult riders in the UK.