Short answer: the Aairsk XT90 is the longest-range bike in the Aairsk line-up. It pairs a 48V 20Ah battery with dual suspension, 26-inch wheels and Shimano 21-speed gearing, and sells for £649.99 with free UK mainland delivery from UK stock. In its standard 250W / 25km/h setting it meets the UK's EAPC rules for use on public roads and cycle paths. Its single strongest feature is range: an estimated 45–60km on throttle alone, or 60–100km with pedal assist.
Disclosure: this review is written by E Bike Market (Horizon and Co Solutions Ltd), which sells the Aairsk XT90. Specifications and range figures are supplied by the manufacturer and are estimates rather than guarantees. We have flagged the weak points as well as the strong ones below.
Aairsk XT90 at a glance
| Price | £649.99, free UK mainland delivery |
|---|---|
| Motor | Selectable 250W / 500W |
| Battery | 48V 20Ah |
| Assisted speed (standard) | 25km/h (15.5mph) — road legal setting |
| Unlocked speed | Up to 40km/h (25mph) — private land only |
| Range (throttle) | 45–60km (28–37 miles) |
| Range (pedal assist) | 60–100km (37–62 miles) |
| Charging time | 6–7 hours |
| Wheels | 26-inch |
| Gearing | Shimano 21-speed |
| Suspension | Dual — front and rear |
| Throttle | Thumb throttle |
| Colour | Black |
| Stock | Held in the UK — no import wait, no customs charge |
Battery and range: the XT90's main argument
Almost every budget electric mountain bike in the UK ships with a 10Ah or 13Ah battery. The XT90 doubles that with a 48V 20Ah pack, which is roughly 960 watt-hours of stored energy. That is the entire reason this bike exists, and it is where your extra money goes.
In practice that means an estimated 45–60km using the throttle alone, and 60–100km if you pedal along with the assistance. For most riders that is the difference between planning your route around the battery and simply not thinking about it.
What actually reduces your range. Manufacturer range figures are measured in favourable conditions, so plan against the lower number. The things that cut into it most are hills, cold weather (a lithium pack loses noticeable capacity below about 5°C), rider and cargo weight, under-inflated tyres, headwinds, and riding constantly in the top assistance level. Stop-start town riding also uses more energy than steady progress, because every acceleration from standstill is the most demanding thing you ask the motor to do.
A full charge takes around 6–7 hours. That is longer than a 10Ah bike, but only because there is more to fill — the charge rate per amp-hour is comparable.
How long will the battery last before it needs replacing?
Expect somewhere around 500–800 full charge cycles before you notice a meaningful drop in capacity, which is typical for lithium-ion e-bike packs and works out at several years for most riders.
A large battery has a quiet advantage here. Because each ride uses a smaller percentage of the total capacity, you put the pack through fewer complete cycles for the same mileage than you would on a 10Ah bike. Over three or four years that difference is real.
To get the most out of it: charge indoors at room temperature, avoid leaving the battery sitting at either 0% or 100% for weeks at a time, and if the bike is being stored over winter, leave the pack at roughly half charge and top it up every couple of months.
Speed, power and UK law — read this part before you buy
The XT90 has a selectable power specification, and understanding it is the most important thing about owning this bike legally.
- 250W / 25km/h (15.5mph) — standard setting. This matches the UK's EAPC (Electrically Assisted Pedal Cycle) specification. In this configuration you can ride on public roads and cycle paths with no registration, no tax, no insurance and no licence. You must be 14 or over, and the bike must have working pedals.
- 500W / up to 40km/h (25mph) — unlocked setting. This is not road legal. In this configuration the bike is legally a motor vehicle, and using it on a public road without registration, insurance and a licence is an offence. Use it only on private land with the landowner's permission.
This is not a technicality that gets quietly overlooked. Riders have been prosecuted for using unlocked e-bikes on public roads, and an insurer will not cover an accident involving one. Check the current GOV.UK electric bike rules, and read our related guide on whether a higher-wattage e-bike is legal if limited to 250W.
Ride quality: suspension, gearing and wheels
The XT90 runs dual suspension — a suspension fork at the front and a rear shock. At this price the suspension is coil-based rather than air-sprung, so it is there to take the sting out of potholes, kerbs, gravel and rutted bridleways rather than to handle technical downhill riding. On broken tarmac and towpaths that is exactly the right amount of suspension, and it is noticeably more comfortable than a hardtail over a long ride.
Shimano 21-speed gearing is a genuine plus at this price, and it matters more on a heavy e-bike than people expect. When the battery runs low, or when you want to extend your range by pedalling, a wide gear range is what makes an e-bike rideable rather than a very heavy bicycle. Seven-speed setups — common on cheaper bikes — leave you spinning out or grinding on gradients.
The 26-inch wheels are a middle-ground choice. They roll over rough ground better than a 20-inch folding e-bike and are more manoeuvrable and easier to store than 29-inch wheels, which is a sensible compromise for mixed road and trail use.
Build quality: what to expect
Being straightforward about this: the XT90 is a budget-tier bike, and the components reflect that. The Shimano drivetrain is a recognised brand; most other parts — the motor, controller, brakes, suspension and display — are manufacturer components rather than named-brand items. That is the norm at this price point across the whole category, and it is how the bike reaches £649.99 with a 20Ah battery.
What that means practically is that the XT90 is well suited to leisure riding, commuting and light trail use, and is not intended to take the punishment of aggressive mountain biking. Keep the drivetrain clean and lubricated, check the brakes and spoke tension after the first 100km of use, and keep the tyres at their recommended pressure — low tyre pressure is the single most common cause of disappointing range.
Value for money
The fairest way to judge the XT90 is on cost per amp-hour. At £649.99 you are paying a premium of roughly a couple of hundred pounds over an entry-level 10Ah electric mountain bike, and in return you get double the battery, dual suspension and a 21-speed drivetrain rather than a 7-speed one.
If you buy a cheaper bike and later decide you need more range, a replacement 48V 20Ah battery on its own typically costs a substantial fraction of the price difference — so if you already know that range matters to you, buying it built in is the better value route.
Where the XT90 is not good value is if your rides are short. If you commute five miles each way, a 10Ah bike will do the job, and you will be carrying the extra weight of a large battery you never use. In that case look at the lighter, cheaper options in our Aairsk GT300 vs GT900 comparison.
Who the Aairsk XT90 suits
Buy it if: range anxiety is your main concern; your routes are hilly; you want to do long leisure rides at weekends; your commute is too far for a 10Ah bike; or you ride on a mix of tarmac, gravel and bridleways and want the comfort of dual suspension.
Look elsewhere if: you need something light enough to carry upstairs or fold into a car boot; your rides are consistently under 15km; or you want a bike for genuine technical mountain biking, which needs a specification well above this price bracket.
Frequently asked questions
Is the Aairsk XT90 road legal in the UK?
Yes, in its standard 250W / 25km/h configuration it meets the UK EAPC specification and can be ridden on public roads and cycle paths without registration, tax, insurance or a licence, provided you are 14 or over. The 500W / 40km/h unlocked configuration is not road legal and is for private land only.
What is the real-world range of the Aairsk XT90?
An estimated 45–60km (28–37 miles) using the throttle alone, and 60–100km (37–62 miles) with pedal assist. Hills, cold weather, rider weight and low tyre pressure will bring those figures down, so plan against the lower end.
How fast does the Aairsk XT90 go?
Assistance cuts out at 25km/h (15.5mph) in the standard road-legal setting. Unlocked, it is capable of up to 40km/h (25mph), which is for private land only.
How long does the battery take to charge?
Around 6–7 hours for a full charge of the 48V 20Ah pack.
How long will the battery last before it needs replacing?
Typically 500–800 full charge cycles before capacity noticeably drops, which is several years of normal use for most riders.
Does it come with a warranty?
Yes — a 12-month warranty, alongside your statutory rights under the Consumer Rights Act 2015 and a 14-day right to cancel under the Consumer Contracts Regulations 2013.
How long is delivery?
The XT90 is held in UK stock, so there is no import wait and no customs charge. Free UK mainland delivery, typically 3–5 working days.
Do I need a licence or insurance?
Not in the 250W road-legal setting — an EAPC is treated as a bicycle. In the unlocked 500W setting the bike is legally a motor vehicle, so road use would require registration, insurance and a licence.
Can I ride it in the rain?
Light rain and wet roads are fine. Avoid deep puddles, jet washing and submerging any part of the electrical system, and dry the bike down afterwards. Store and charge the battery indoors.
Verdict
The Aairsk XT90 is a focused bike with one clear purpose: it removes range as a limitation. If that is your problem, it solves it more cheaply than any other route — and the dual suspension and Shimano 21-speed gearing are meaningful extras rather than marketing. If your rides are short, the extra battery is weight and cost you will not use.
At £649.99 from UK stock, with a 12-month warranty and a road-legal 250W setting, it is a sensible choice for anyone whose main frustration with electric bikes has been running out of charge.
Next steps
- View the Aairsk XT90 Electric Mountain Bike — £649.99, UK stock
- Compare with the Aairsk GT300 vs GT900
- Work out what you actually need with the e-bike battery range calculator
- Browse the full electric bike range