Battery System
BATTERY SYSTEM
Maxon BIKEDRIVE AIR S with 400Wh internal battery and optional 250Wh range extender. Swiss precision engineering meets all-day trail capability in the lightest mid-drive system on the market.
⚡ Maxon BIKEDRIVE AIR S
The Maxon BIKEDRIVE AIR S is designed and manufactured in Switzerland by maxon, a company with decades of experience building precision motors for medical devices, aerospace, and robotics. At 2 kg, it is the lightest mid-drive motor on the market — yet delivers 90 Nm of torque and a peak output of 620 W at 85 rpm with 150-250 W adjustable rider input (default ~200 W).
Unlike conventional e-bike motors, the Maxon uses a concentric design with zero drag when unpowered. When the battery runs out, you're riding a normal bike — not fighting a seized motor. The power cutoff responds within milliseconds of stopping pedaling, giving a natural ride feel that heavier systems cannot match.
Motor Specifications
- Peak Torque 90 Nm
- Peak Power 620 W @ 150-250 W rider input
- Nominal Power 250W (EU legal)
- Motor Weight 2 kg
- Efficiency 89%
- Drag When Off Zero
- Throttle Behaviour Never throttles
Torque Sensor
- Type Proportional
- Rider Input Range 150–250W
- Response Time <10 ms
- Assist Modes ECO / TRAIL / BOOST
- Configurable Via Maxon App
- Effect More input = more range
No Thermal Throttling — Ever
Most e-bike motors overheat during sustained climbs and firmware reduces power output — sometimes by as much as 83%. The Shimano EP801 throttles after just 10 minutes to 17% output. The Brose S Mag drops to 45% after 6 minutes.
The Maxon BIKEDRIVE AIR S never throttles. Its thermal management is engineered to sustain full power output indefinitely. On a 1000m climb, you get the same power at the top as you did at the bottom. This is the single biggest advantage of the Maxon system on real mountain terrain.
🔋 Battery Configuration
The Paratu CP ships with a 400Wh internal battery fully integrated into the downtube. An optional 250Wh range extender mounts inside the frame, bringing total capacity to 650Wh without external packs or bolt-on solutions.
Internal Battery
400Wh lithium-ion, ~2.0 kg, fully integrated in downtube. Provides 35–90+ km depending on terrain, mode, and rider weight.
Range Extender
250Wh add-on, ~1.3 kg, mounts inside the frame triangle. System draws from extender first, preserving the internal battery for the ride home.
Combined 650Wh
Total system weight under 4.5 kg for motor + 650Wh battery. Competitors need 700–840Wh and weigh 6–8 kg for similar range.
💡 Intelligent Power Management
The Maxon system uses a proportional torque sensor — it measures exactly how hard you're pedaling and scales motor assist accordingly. This is fundamentally different from cadence sensors that simply detect whether you're pedaling.
Higher rider input = less motor share = more range. A rider putting in 250W will see 15–20% more range than one at 150W in BOOST mode, because the motor doesn't need to work as hard. The rider input target is configurable in the Maxon app from 150W to 250W.
The system also draws from the range extender first, preserving the internal battery. This means even on long rides, you always have reserve power for the ride back to the trailhead.
🌡 Temperature Performance
Lithium-ion batteries perform best between 10°C and 35°C. Below freezing, capacity drops significantly. The Maxon system's efficiency advantage means you retain usable range even in cold conditions where competitors become impractical.
⚖ System Weight Comparison
The real advantage of the Maxon system shows in total system weight. A Paratu CP at 19 kg with 400Wh delivers competitive range to bikes weighing 23–24 kg with 800Wh batteries — because efficiency and weight matter more than raw battery capacity.
| System | Bike Weight | Battery | Motor + Bat Weight | Throttles? |
|---|---|---|---|---|
| Paratu CP + Maxon AIR S DIRTLAB | 17–19 kg | 400 / 650 Wh | ~4.0 / 5.3 kg | Never |
| Amflow PL + DJI Avinox | 20.3 kg | 800 Wh | ~6.5 kg | 18 min → 47% |
| Santa Cruz Heckler + Shimano EP801 | 22.4 kg | 720 Wh | ~6.8 kg | 10 min → 17% |
| Trek Rail+ + Bosch CX Gen 5 | 24.1 kg | 800 Wh | ~7.2 kg | 15 min → 65% |
| Specialized Levo Gen 3 + Brose S Mag | 22.0 kg | 700 Wh | ~6.9 kg | 6 min → 45% |
| Specialized Levo Gen 4 + Spec 3.1 | 23.7 kg | 840 Wh | ~7.5 kg | 18 min → 78% |
| Canyon Spectral:ONfly + TQ HPR 50 | 18.5 kg | 360 Wh | ~4.2 kg | 15 min → 33% |
Calculate Your Range
Use our interactive Range Calculator to estimate real-world range based on your weight, terrain, elevation, temperature, and assist mode. Compare the Maxon system against 9 competitor motors using real test data from emtb-test.com.
See It in Action
Verified Range Performance
Range data independently verified by emtb-test.com (Ludwig Dohl, February 2026).
Maxon BIKEDRIVE AIR S Motor Specifications
| Peak Power | 620W |
| Max Torque | 90 Nm |
| Max Assist Ratio | 400% |
| Motor Weight | 2 kg |
| Battery (Internal) | 400Wh |
| Range Extender | +250Wh (total 650Wh) |
Frequently Asked Questions
How far can I ride on a single charge?
Independent testing by emtb-test.com verified 1,056 height meters in full power mode with the 400Wh battery. In mid mode, expect approximately 1,300 Hm — comparable to what competitors achieve at full power with 700Wh batteries. The lighter overall bike weight (19.5 kg) means less energy consumed per meter of climbing.
Why only 400Wh when competitors have 700-750Wh?
Weight. A 700Wh battery adds approximately 2.5 kg to the bike. The Paratu CP strategy prioritises ride quality: lighter weight means better handling, less fatigue, and — counterintuitively — comparable real-world range because you consume less energy moving a lighter machine uphill. For big days, the 250Wh range extender brings total capacity to 650Wh.
Can I charge while riding?
No. The Maxon system does not support regenerative braking or riding-while-charging. This is by design — regen systems add motor drag and weight with minimal real-world benefit on MTB terrain. A full charge from empty takes approximately 3.5 hours (400Wh) via the included charger.
Is the range extender hot-swappable on the trail?
Yes. The 250Wh range extender mounts externally and can be added or removed without tools. Carry it in a pack for longer rides and attach when the main battery depletes. The system seamlessly switches to the extender with no power interruption.
What is the battery warranty and lifespan?
The Maxon battery is warrantied for 2 years or 500 full charge cycles, whichever comes first. At 500 cycles the battery retains approximately 80% of its original capacity. Real-world lifespan typically exceeds 800 cycles before noticeable range degradation. Replacement batteries are available through our spare parts programme.