Maxon BIKEDRIVE AIR S
BIKEDRIVE
AIR S
The lightest, most natural e-MTB drive system. Swiss precision engineered for riders who refuse to compromise.
Why this motor works on a Dirtlab frame
The Maxon BIKEDRIVE AIR S was designed as a lightweight, quiet, efficient unit — not a power statement. Dirtlab builds its eMTB frameset, the Paratu CP, around that character, not against it. The Concentric Pivot geometry places the main pivot at the centre of the rear axle, which turns the motor’s smoothness into a felt ride quality:
- Zero-bob on the climb — suspension stays still under pedal power, no lockout needed. Every watt moves you forward.
- DriveRelief under motor torque — chain growth is calibrated through full travel, so the motor runs clean stroke-to-stroke. The consumer-facing name for the feel is ZeroKickback: no pedal feedback, geometrically eliminated, not tuned.
- Groundtracing on the descent — the rear wheel reads terrain and climbs obstacles rather than deflecting off them.
This is what we mean by Made at the Source: our carbon frame, our kinematics, our assembly in Taichung — designed together with Maxon’s Swiss-engineered mid-drive, not retrofitted to it.
Why We Chose Maxon
When we set out to build the Dirtlab eMTB, one principle was non-negotiable: it must ride like a real mountain bike. That meant the motor had to disappear. No rubber-band pedal lag, no artificial surging, no extra 3 kg hanging off the bottom bracket.
Maxon has spent 60+ years building precision motors for the most demanding environments on Earth—and beyond. Their drives are on every NASA Mars rover since Sojourner. The BIKEDRIVE AIR S brings that same obsessive engineering to the trail.
At 2 kg, it is the lightest mid-drive motor on the market. The concentric design preserves a perfect chainline, and the torque response is instant and linear. When you stop pedalling, assist cuts within milliseconds. The result is a ride that feels organic—power when you want it, silence when you don't.
Swiss Precision
Designed and built in Obwalden, Switzerland. Every component held to aerospace tolerances.
Lightest in Class
At 2 kg, it undercuts every competitor mid-drive by over 600 g. You feel the difference on every climb.
Concentric Design
Motor wraps around the bottom bracket axle, keeping the chainline perfect and Q-factor narrow.
Whisper Quiet
Under 65 dB at full load. On the trail, you hear your tires and the wind—not your motor.
Trail-Built, Not Repurposed
Engineered from scratch for demanding MTB use. Sealed bearings, impact-resistant housing, integrated shift detection.
Full Specifications
Every number, verified. No marketing fluff.
| Motor Type | Mid-drive, concentric |
| Nominal Power | 250 W |
| Peak Power | 620 W |
| Maximum Torque | 90 Nm |
| Motor Weight | 2 kg |
| System Weight (w/ 400 Wh battery) | ~4.5 kg |
| Battery Options | 400 Wh internal + 250 Wh range extender |
| Support Levels | 4 (Level 0, I, II, III — per Maxon BIKEDRIVE) |
| Connectivity | Bluetooth LE, ANT+ |
| Display / Control | Minimal bar-mounted remote + smartphone app |
| Noise Level | < 65 dB |
| Gear Sensor | Integrated shift detection |
| Certification | EN 15194 (EU pedelec) |
Battery System
Modular energy. Go light for quick laps, or load up for all-day epics.
Internal Battery
Compact lithium-ion pack integrated seamlessly into the downtube. Invisible from the outside, perfectly balanced at the bike's center of gravity.
~2.0 kgRange Extender
Bottle-cage mounted auxiliary pack. Hot-swappable on the trail without tools. Carry a spare in your pack for truly remote rides.
~1.3 kgCombined Capacity
Run both packs together for maximum range. The system draws from the range extender first, preserving the internal battery for the ride home.
Full-day capabilityFour levels — pick what you need
Maxon BIKEDRIVE AIR S uses four official Support Levels. Switch on the fly with the + / − buttons on the POWERTAB. The full 90 Nm / 620 W / 400% system peak is reached at Level III.
Level 0
System on, motor off. Use on descents, flats, or for training. No range cost — you ride entirely under your own power, with no resistance.
Level I
Range-focused. Gentle, natural support. Best for long distance and modest hills — the level that maximises battery life.
Level II
Balanced support. The everyday-trail level. Responsive on climbs, efficient enough for full-day rides.
Level III
Climb-focused. Maximum support for steep ascents and technical pitches. The full system peak: 90 Nm / 620 W / 400% assist.
Power per level is fully customisable via the BIKEDRIVE Connect app. Names “Eco/Trail/Boost/Turbo” are not Maxon’s official terminology — the system uses Levels 0–III.
vs The Competition
An honest look at how the BIKEDRIVE AIR S compares to the most popular mid-drive systems on the market.
| Specification | Maxon AIR S | Shimano EP801 | Bosch CX Gen5 | Fazua Ride 60 |
|---|---|---|---|---|
| Motor Weight | 2 kg | 2.6 kg | 2.8 kg | 1.96 kg |
| Max Torque | 90 Nm | 85 Nm | 85 Nm | 60 Nm |
| Peak Power | 620 W | 600 W | 600 W | 600 W |
| Noise Level | < 65 dB | ~72 dB | ~73 dB | ~67 dB |
| Natural Feel | ★★★★★ | ★★★☆☆ | ★★★☆☆ | ★★★★☆ |
| Concentric Design | Yes | No | No | Yes |
| Range Extender | 250 Wh add-on | No | PowerMore 250 | No |
| Best For | Light eMTB / trail | Aggressive enduro | All-round / touring | Light eMTB / gravel |
Note: The AIR S prioritizes natural ride feel and low weight over raw torque. If you need 85 Nm for shuttle-style riding, this isn't the motor for you—and that's by design. We build mountain bikes, not motorcycles.
Built Into Every Dirtlab
The BIKEDRIVE AIR S isn't bolted on as an afterthought. It's designed around our Paratu CP carbon platform from day one.
Carbon Frame Integration
The Paratu CP frame is molded specifically around the AIR S motor envelope. No adapter plates, no compromised geometry. The motor becomes part of the chassis.
Clean Cable Routing
All motor harness cables, battery connectors, and sensor wires route internally through the frame. From the outside, it looks like a regular mountain bike.
Zero Suspension Impact
The concentric motor placement ensures no interference with K-Volve suspension kinematics. Anti-squat, leverage ratio, and axle path remain exactly as designed.
Removable Motor Unit
Four bolts and two connectors. The entire motor can be removed in under 10 minutes for service, firmware updates, or converting to a fully analog bike.
Independent Analysis
Maxon BikeDrive Air S
EMTB-Test.com Verdict
“It’s as punchy as a Shimano EP801 motor and quieter than TQ’s HPR 60. The Maxon Drive Air S lays down a new benchmark in the full-power motor category.”
— Ludwig Dohl, emtb-test.com — Feb 2026
“The Dirtlab/Maxon collab puts mountain biking and the outdoor experience front and centre — not some arms race for maximum performance.”
— emtb-test.com — Philosophy Assessment
“Whether it’s assisting or you’re trail-surfing on the way down, you don’t hear a thing.”
— Ludwig Dohl, emtb-test.com / @ridebetterbikes — Noise Assessment, Feb 2026
Official specifications: 620W peak, 90 Nm torque, 400% max assist, 2 kg motor weight.
Already own a Maxon-equipped Dirtlab?
Maxon BIKEDRIVE Support hub
LED reference · troubleshooter · battery care · range extender · BIKEDRIVE Connect app guide. Most issues resolve in under 5 minutes with our self-service guides.
Open the Support hub →emtb-test.com Verdict
“It’s as punchy as a Shimano EP801 motor and quieter than TQ’s HPR 60 — while weighing less than both.”
— Ludwig Dohl, emtb-test.com / YouTube: @ridebetterbikes, February 2026
“The motor is just a means to an end — it does its job without making itself the centre of attention. That’s exactly what a trail motor should be.”
— Ludwig Dohl, emtb-test.com / YouTube: @ridebetterbikes, February 2026