S-EDF 90mm vs 105mm vs 120mm: Ultimate RC EDF Fan Comparison Guide 2026

January 22, 2026

Comparing S-EDF 90mm, 105mm, and 120mm Ducted Fan Systems: Which One Fits Your RC Jet?

If you're deep into the world of RC jets and EDF (Electric Ducted Fan) systems, you've likely come across the S-EDF series. Today, we’ll take a detailed look at three popular models—the S-EDF 90mm, 105mm, and 120mm—and compare their specifications, performance, and ideal use cases.

1. Overview & Key Specifications

Feature	S-EDF 90mm	S-EDF 105mm	S-EDF 120mm
Motor Model	3560, 1550KV (External)	4270, 750KV (External)	5268, 640KV (Internal)
Total Weight	~320g	636g	858g
Blade Count	12	11	10
Blade Type	Vortex	Vortex	Vortex
Plug Type	Banana 4.0	Banana 6.0	Banana 6.0
Recommended Battery	6S, 5200mAh, 60C	6S×2, 5200mAh, 60C	6S×2, 5200mAh, 60C
Recommended ESC	100A	160A	160A

2. Motor Installation Parameters

Parameter	90mm	105mm	120mm
Motor Output Shaft	6mm	8mm	8mm
Motor Shaft Length	15mm	17mm	20mm
Mounting Hole Distance	25mm	25mm	30mm
Mounting Hole Diameter	M4	M4	M4

3. Performance Testing (Push Balance)

Test Parameter	90mm	105mm	120mm
Test Battery	6S, 5200mAh, 60C	12S, 5200mAh, 60C	12S, 5200mAh, 60C
Test Current	95A	118A	120A
Max Thrust	3.7kg	7.4kg	8.6kg

🔹 S-EDF 90mm (12S Version)

Best For: High-performance 90mm jets where space is limited but power is critical.
Power Setup: 12S battery (dual 6S), delivering much higher voltage and efficiency.
Thrust: 5.0kg – a significant 35% increase over the 6S version.
Note: Higher voltage means higher efficiency (78A vs 95A for similar power class), but requires HV ESC and robust wiring.

4. Quick Comparison Table: S-EDF 90mm, 105mm, 120mm

Model	Motor & KV	Battery	Max Thrust	Weight	Recommended ESC
S-EDF 90mm (6S)	3560, 1550KV	6S LiPo	3.7kg	~320g	100A
S-EDF 90mm (12S)	4250, 950KV	12S LiPo	5.0kg	400g	100–120A HV
S-EDF 105mm	4270, 750KV	12S LiPo	7.4kg	636g	160A
S-EDF 120mm	5268, 640KV	12S LiPo	8.6kg	858g	160A

5. Which One Should You Choose?

Choose the 90mm (6S) if you’re building a lightweight jet and want a simple, affordable power system.
Choose the 90mm (12S) if you want max performance from a 90mm unit and are ready for a high-voltage setup.
Choose the 105mm if you need more thrust for a larger airframe but want to stay under 120mm size.
Choose the 120mm if you’re building a large, heavy jet and need maximum thrust and presence.

Installation Tips for S-EDF Systems

All S-EDF models use M4 mounting holes, but shaft sizes and lengths vary:

90mm: 6mm shaft, 15mm length
105mm: 8mm shaft, 17mm length
120mm: 8mm shaft, 20mm length

Always check your motor mount compatibility and use a high-quality ESC matched to the recommended current.

FAQ: S-EDF EDF Systems

❓ What battery should I use with S-EDF?

90mm (6S): 6S 5200mAh 60C
90mm (12S): 12S 5000mAh
105mm & 120mm: 12S 5200mAh 60C (dual 6S)

❓ Can I run a 90mm 12S on a 6S battery?

No, the 12S version is designed for high voltage. Use the correct battery to avoid damage.

❓ Which S-EDF is the most efficient?

The 90mm 12S version runs at 78A for 5kg thrust, offering excellent efficiency for its size.

❓ Is the 120mm worth the extra weight?

If you need 8.6kg thrust for a large jet, yes. For smaller models, the 105mm may be a better fit.

Conclusion: Which S-EDF Should You Buy?

The S-EDF series offers a versatile range of EDF systems for RC jet enthusiasts. Whether you're building a lightweight sport jet or a large-scale turbine model, there's an S-EDF that fits your needs.