Servo Efficiency
A curated selection of servos tested and ranked for ornithopter use.
Efficiency = Torque / (Weight × Speed). Eff/€ = Efficiency per , scaled by ∛torque for fairness across sizes.
Higher is better. Click column headers to sort — Shift+click for multi-column sort. Drag the voltage slider to narrow. Submit additions per PR to _data/servos.yml.
| Servo | V | Weight g | Torque kg/cm | Speed s/60° | Efficiency | Price | Eff/€ | Flight Performance | Notes |
|---|---|---|---|---|---|---|---|---|---|
| KST DS 113 MG | 4.8 | 12.0 | 1.80 | 0.14 | 1.07 | €14.30 | 0.09 | Untested | |
| Blue Arrow D05023MG | 4.8 | 5.4 | 1.50 | 0.06 | 4.63 | €12.00 | 0.44 | Untested | Slow under load |
| Blue Arrow D43S-6.0-MG | 5.0 | 5.6 | 1.48 | 0.05 | 5.51 | €11.00 | 0.57 | Untested | |
| Blue Arrow D05023MG | 5.0 | 5.4 | 1.23 | 0.04 | 5.06 | €12.00 | 0.45 | Untested | |
| Blue Arrow AF D43S-6.0-MG | 6.0 | 5.6 | 1.76 | 0.04 | 7.67 | €11.00 | 0.84 | Strong Flight 📺📺📺📺📺📺 | Up to 6.2V. Gralha Azul 28g, Seraphim 31g. SFO86, SFO87, Butterfly88 |
| Blue Arrow D05023MG | 6.0 | 5.4 | 1.42 | 0.04 | 6.57 | €12.00 | 0.62 | Untested | |
| Spektrum H2060 | 6.0 | 4.0 | 0.82 | 0.07 | 2.93 | €16.00 | 0.17 | Untested | Ultra-light 4g |
| Blue Arrow D03013 | 6.0 | 3.0 | 0.65 | 0.06 | 3.61 | €13.10 | 0.24 | Untested | Ultra-light 3g |
| VOTIK PTK 7350 MG-D | 7.4 | 5.5 | 1.80 | 0.07 | 4.68 | €5.50 | 1.03 | Best efficiency/€ | |
| VOTIK PTK 7465 / 7465W MG | 7.4 | 9.0 | 5.00 | 0.10 | 5.56 | €7.00 | 0.46 | Untested | HV coreless, metal gear, waterproof, 180°, 25T. 5kg = stall torque; effective torque lower. Most flights at 8.4V — see 8.4V entry for flight, jitter tuning, durability. |
| VOTIK PTK 7465 / 7465W MG | 8.4 | 9.0 | 5.70 | 0.09 | 7.04 | €7.00 | 0.56 | Strong Flight 📺📺📺📺📺 | 8.4V spec — most flights at this voltage. Kestrel 45g, Albatross 57g, Butterfly 54g, Entomoid. SFOArchaeopteryx153 53g. Slow but good torque, no gear damage so far; jitters when stopped but no problems during flapping. Durability testing ongoing. Jitter fix: increase deadband (degrades accuracy, fine for flapping) or reduce gain + increase damping (slower flapping), via PTK programming card + PTK Programming Software V2.1.3 or PTK programmer's box. |
| VOTIK PTK 7465 Plus | 7.4 | 9.0 | 7.50 | 0.08 | 10.42 | €10.00 | 0.53 | Untested | Upgraded 7465 — higher torque (7.5kg stall), faster. Specs need verification. |
| Blue Arrow D0576HT-MG-HV | 7.4 | 7.9 | 4.20 | 0.06 | 9.49 | €20.00 | 0.77 | Strong Flight 📺📺📺 | Inservos D0576HT-MG-HV = older batch. White Heron 44g 1175mm. E20FnTzsE6o: oversized model. Fenghuangopterus 1096mm. Nycto also uses this servo (not flown high yet). |
| RYservo DS08 | 8.4 | 3.20 | 0.06 | Not recommended for flapping | Torque slightly lower than BlueArrow D0576HT. Failed during testing (stopped working, replaced). Final judgment pending. | ||||
| Inservos D0474HT-MG-HV | 7.4 | 7.3 | 3.60 | 0.08 | 6.16 | €23.00 | 0.41 | Okay Flight | |
| Blue Bird BMS-126WV | 7.4 | 11.3 | 6.50 | 0.07 | 8.22 | €20.00 | 0.77 | Untested | New 2024 WV series |
| Blue Bird BMS-127WV | 7.4 | 11.3 | 4.80 | 0.05 | 8.50 | €20.00 | 0.72 | Untested | New WV series, slower but precise |
| Blue Bird BMS-115WV | 7.4 | 11.1 | 7.10 | 0.09 | 7.11 | €20.00 | 0.68 | Untested | |
| Blue Bird BMS-125WV | 7.4 | 11.3 | 7.10 | 0.09 | 6.98 | €20.00 | 0.67 | Untested | Like 115WV, sub-zero rated |
| Blue Bird BMS-207WV | 7.4 | 17.5 | 7.50 | 0.05 | 8.57 | €25.00 | 0.67 | Untested | |
| Blue Bird BMS-M15S | 7.4 | 13.8 | 7.50 | 0.10 | 5.43 | €16.00 | 0.66 | Untested | Great value mid-weight |
| Blue Bird BMS-115HV | 7.4 | 11.3 | 5.40 | 0.10 | 4.78 | €18.00 | 0.47 | Untested | |
| Blue Bird BMS-107HV | 7.4 | 10.5 | 2.50 | 0.05 | 4.76 | €13.00 | 0.50 | Untested | Entry-level WV |
| SAVÖX SV-1270TG | 7.4 | 56.0 | 35.00 | 0.11 | Strong Flight 📺📺 | Titanium gear, coreless, HV. Standard-size. Takemura runs at 12.6V (3S) overvolt successfully — see 12.6V entry. | |||
| SAVÖX SV-1270TG (3S overvolt) | 12.6 | 56.0 | 35.00 | 0.08 | Strong Flight 📺 | Overvolted 3S (rated 7.4V). Takemura — tried connecting 3cell to servo rated at 7.4V... works well. By raising servo voltage, thrust was improved. 315g AUW, 1800mm span. Use at own risk. | |||
| Blue Arrow X-4 HTMG HV | 8.4 | 7.4 | 3.20 | 0.07 | 6.18 | €33.00 | 0.28 | Untested | |
| JX DHV56MG | 7.4 | 5.6 | 1.20 | 0.10 | 2.14 | €8.15 | 0.28 | Untested | Budget 5.6g option |
| KST MR320 | 7.4 | 21.0 | 5.50 | 0.08 | 3.27 | €36.00 | 0.16 | Good Flight | Magnet potentiometer. Wider horn operating angle than MS320 → better flight performance. MS320 is newer version with similar specs. |
| KST MS320 | 7.4 | 21.0 | 5.50 | 0.08 | 3.27 | €36.00 | 0.16 | Good Flight 📺 | Newer version of MR320 |
| KST X08 Plus V5 | 7.4 | 9.0 | 4.85 | 0.12 | 4.49 | €43.00 | 0.18 | Untested | Premium 9g, excellent build |
| KST DS215MG | 7.4 | 20.0 | 3.70 | 0.05 | 3.70 | €33.50 | 0.17 | Untested | |
| SAVÖX SV-1232MG | 7.4 | 23.0 | 5.00 | 0.05 | 4.35 | €23.00 | 0.32 | Untested | |
| Blue Arrow MI CS 9-6F MG | 7.4 | 7.6 | 2.68 | 0.05 | 7.46 | €19.50 | 0.53 | Untested | Magnet potentiometer |
| Blue Arrow MI CS 9-6 MG | 7.4 | 7.9 | 3.60 | 0.07 | 6.24 | €19.50 | 0.49 | Untested | Magnet potentiometer |
| ROBSG HS1106S | 7.4 | 20.3 | 9.50 | 0.05 | 9.36 | €28.00 | 0.71 | Untested | Flight tested — weak gears |
| DUALSKY DS169F | 7.4 | 9.0 | 2.80 | 0.06 | 5.19 | €30.99 | 0.24 | Untested | |
| Petoi P1S | 7.4 | 14.0 | 3.00 | 0.07 | 3.06 | €14.00 | 0.32 | Untested | |
| Blue Arrow X-4 HTMG HV | 8.4 | 7.3 | 3.40 | 0.04 | 10.83 | Untested | Highest raw efficiency in class; factory price only | ||
| DEMAND DBS6084V | 8.4 | 80.0 | 60.00 | 0.15 | 5.00 | Weak Flight 📺 | Kazu's Pteranodon 131 (232cm, 325g AUW). Stall torque 60 kg·cm. Speed estimated — verify. | ||
| HDKJ D3625MG | 7.4 | 67.0 | 26.00 | 0.07 | 5.54 | €21.00 | 0.78 | Untested | Waterproof; large but excellent value |