Maxon BIKEDRIVE AIR S
Maxon BIKEDRIVE AIR S — Tests & Motor Explainer
Credit: emtb-test.com / @ridebetterbikes
Review available in German and English — select via YouTube captions.
Credit: Maxon (official)
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 kgInternal Battery 600
The bigger downtube battery for long days: 50% more energy than the 400 Wh pack in the same integrated position. Pre-order now, delivery Q4 2026.
~3.3 kg · pre-orderRange Extender
Bottle-cage mounted auxiliary pack. Hot-swappable on the trail without tools. Carry a spare in your pack for truly remote rides.
1.6 kgCombined 400 + 250
The 400 Wh internal battery plus the 250 Wh range extender. Light setup for long rides: carry the extender only when you need it.
~3.6 kg battery weightCombined 600 + 250
The 600 Wh internal battery plus the 250 Wh range extender. 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 capabilityHow far does it go?
Benchmark from the logged rides of our test rider Peter Gratzl in the Alps: 10 rides, 328 km and 15,153 m of climbing on the 400 Wh battery, on average 10.4 Wh per km with 46 m of climbing per km. Rider 88 kg, bike and rider about 109 kg. Range below = 95% of the battery, at his average and from his easiest to his hardest ride.
| Battery | Typical | Climbing | Easy ↔ hard |
|---|---|---|---|
| 400 Wh | ~37 km | ~1,700 m | 21–54 km |
| 600 Wh | ~55 km | ~2,500 m | 31–80 km |
| 650 Wh 400 + 250 |
~59 km | ~2,750 m | 33–87 km |
| 850 Wh 600 + 250 |
~78 km | ~3,600 m | 44–114 km |
Your range depends on assist level, rider weight, terrain, temperature and tyres. 600 Wh and 850 Wh are extrapolated from the same rides (pre-order, delivery Q4 2026).
Four 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 current mid-drive systems (status October 2026).
| Specification | Maxon AIR S | DJI Avinox M2S | Bosch CX Gen5 | Shimano EP801 | Mahle M40 | Gobao P120 | TQ HPR60 | Fazua Ride 60 |
|---|---|---|---|---|---|---|---|---|
| Motor weight | 2.0 kg | 2.59 kg | 2.8 kg | 2.7 kg | 2.5 kg | 2.85 kg | 1.92 kg | 1.96 kg |
| Max torque | 90 Nm | 130 Nm (150 Boost) | 100 Nm | 85 Nm | 105 Nm | 110 Nm (120 Boost) | 60 Nm | 60 Nm |
| Peak power | 620 W | 1300 W (1500 Boost) | 750 W | n/a | 850 W | 850 W | 350 W | 450 W |
| Range extender | Yes, 250 Wh | n/a | PowerMore 250* | No | No (iM8 800 Wh battery) | n/a | Yes, 160 Wh | n/a |
| Class | Full power, light weight | Full power | Full power | Full power | Full power | Full power | Light | Light / mid |
| Quietness (emtb-test.com, by ear) | Quietest tested | Noticeably louder | Noticeably louder | Noticeably louder | not tested | not tested | Louder than Maxon | not tested |
The AIR S is the lightest full-power motor in this table. Several newer motors offer more torque and peak power on paper; the AIR S trades that for low weight, a quiet drive and natural power delivery. emtb-test.com: “No motor delivers its power more discreetly.”
Figures: manufacturer data; Avinox, Gobao, Bosch, TQ HPR50/60 and Fazua as published by the makers or quoted by trade press (2025/26). Bosch CX Gen5: BDU384Y after the free 2025 update. Avinox M2S peak only in 60-second Boost. *PowerMore 250: Bosch SmartSystem range extender, fit to CX to be confirmed per bike. Quietness: emtb-test.com motor ranking by ear, no dB values published.
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.
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.
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