T-HOBBY AM670 Brushless Motor Buying Guide
Why Choose the T-HOBBY AM670?
The T-HOBBY AM670 is built for a larger class of 3D aircraft than the AM600. It is specifically designed around 67–70 inch aerobatic planes, with an intended all-up aircraft weight of approximately 4.2–5.2kg in the AM670 power system.
The main advantage is the combination of high thrust, fast response and controlled motor weight.
At approximately 416g, the AM670 remains relatively light for a motor in this power class. Its large-diameter construction provides the torque required for large propellers, while the open-back structure improves airflow around the stator.
T-HOBBY also states that the updated structure increases overall strength by 15% while reducing weight by 44g compared with the previous design.
480KV vs 520KV
The AM670 is available in 480KV and 520KV versions. Both are designed for 6S power systems, but the two windings can be used to achieve slightly different flight characteristics.
| Version | Battery | Flight Direction | Recommended Propeller | Best For |
|---|
| 480KV | 6S | Lower-RPM, controlled response | 18×10 | Efficient/high-thrust 3D setup |
| 520KV | 6S | Higher-RPM, faster response | 18×8 | Aggressive 3D / rapid throttle response |
T-HOBBY's AM670 power-combo recommendations pair the 480KV version with an 18×10 propeller and the 520KV version with an 18×8 propeller.
For pilots prioritizing a more controlled power delivery and efficient large-prop setup, 480KV is a practical choice. If faster response and more aggressive aerobatic handling are the priority, 520KV is the more natural option.
6S Power System for 67–70" Aircraft
The AM670 is designed specifically around a 6S power system rather than a high-voltage setup.
A typical system can be configured as:
6S LiPo → AM116A ESC → AM670 → 18" Carbon Propeller
T-HOBBY recommends a 6S 4000–5000mAh 70C+ LiPo battery for the AM670 power system. The higher discharge capability is important when the aircraft is being flown aggressively and the motor is required to deliver high instantaneous power.
The recommended aircraft weight range is approximately 4.2–5.2kg, so battery selection should also consider the final all-up weight rather than capacity alone.
416g Motor Weight for a Large 3D Plane
At approximately 416g, the AM670 is designed to provide a strong power-to-weight balance for 67–70 inch aircraft.
For this class of plane, simply choosing the most powerful motor available is not necessarily the best solution. Excess motor weight increases the aircraft's overall mass and can affect its balance and handling.
The AM670 instead combines a large motor structure with weight reduction and an open-back design, aiming to provide the power required for aggressive 3D flight without excessive motor mass.
Recommended AM670 Power System
| Component | Recommended Choice |
|---|
| Aircraft | 67–70" 3D aerobatic plane |
| Motor | T-HOBBY AM670 |
| KV | 480KV / 520KV |
| Battery | 6S 4000–5000mAh 70C+ LiPo |
| ESC | AM116A |
| Propeller | 18×8 / 18×10 carbon |
| Aircraft Weight | Approx. 4.2–5.2kg |
| Maximum Thrust | Up to 10.1kg |
| Motor Weight | Approx. 416g |
These specifications follow T-HOBBY's recommended AM670 power-system configuration.
Final Recommendation
The T-HOBBY AM670 is a purpose-built power solution for pilots flying 67–70 inch 3D aerobatic aircraft and looking for substantial thrust reserve without moving to a much heavier motor class.
Choose 480KV when you want a more controlled large-prop setup with the recommended 18×10 propeller. Choose 520KV when faster motor response and aggressive 3D performance are the priority, using the recommended 18×8 propeller.
For a complete build, the straightforward combination is:
AM670 + AM116A + 6S 4000–5000mAh 70C+ LiPo + 18" carbon propeller
With up to 10.1kg of specified extreme thrust, a 416g motor structure and dedicated compatibility with 67–70 inch 3D planes, the AM670 is best suited to pilots who need high torque, rapid response and strong thrust reserve for demanding aerobatic flight.
T-HOBBY AM116A 3D Brushless ESC For Fixed Wing CompetitionAM116A$144.53 Save $4.47
Verified