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SunnySky X4120

hobby uav brushless motor. Specs read from manufacturer page ↗.

27.91TWR
22.16EFTWR
8.15Thrust kg
0.292Weight kg
A$152.31Best price

advertised This thrust figure is the one the vendor advertises, read from their product copy. The throttle setting, propeller and cell count behind it are frequently unstated, so it is a guide rather than a measurement.

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Specifications

BrandSunnySky
ModelX4120
Stator4120
Weight292 g
Max thrust8,150 g
Max current97.0 A
Max power2,425 W
Peak power2,435 W
No-load current1.50 A
Winding resistance0.022 Ω
Max RPM9,078
Hover efficiency5.19 g/W
Peak-throttle efficiency3.35 g/W
Gradehobby
Applicationuav
Data confidencereported
Thrust basisreported
Efficiency basisreported
Measured test points17

Measured thrust curve

4,0758,150 2,435 W 0 W
Thrust (g) against electrical input power (W), 17 measured points from the manufacturer's test table.

Where to buy

VendorPriceAs listedStockLead days
SunnySky USA USA$152.31USD 105.99in stock12buy ↗
SunnySky USA USA$152.31USD 105.99backorder42buy ↗
SunnySky USA USA$152.31USD 105.99in stock12buy ↗
SunnySky USA USA$152.31USD 105.99in stock12buy ↗
SunnySky USA USA$152.31USD 105.99backorder42buy ↗
SunnySky USA USA$152.31USD 105.99in stock12buy ↗

Multi-pack listings are shown at their per-unit price so they stay comparable.

Thrust test points

PropellerCellsThrust gg/WBasis
unspecified—8,1503.35reported
unspecified—7,0003.52reported
unspecified—6,0004.01reported
unspecified—5,0004.56reported
unspecified—4,0005.19reported
unspecified—3,5005.56reported
unspecified—3,0006.00reported
unspecified—2,7506.21reported
unspecified—2,5006.49reported
unspecified—2,2506.72reported
unspecified—2,0007.08reported
unspecified—1,7507.37reported
unspecified—1,5007.89reported
unspecified—1,2508.33reported
unspecified—1,0009.09reported
unspecified—7509.68reported
unspecified—50010.00reported

Compatible accessories

Parts this catalogue holds that fit this component, and the evidence behind each pairing. Fit is inferred from published specifications, not from having tried it. Confirm mounting and clearance before you buy.

rule of thumb The size conventionally run on a stator this big. Not a measurement -- check clearance and current draw before flying it.

CAD model

No CAD model linked yet.

How the metrics are calculated

TWR is max thrust divided by motor weight, motor only, static, excluding propeller and ESC. EFTWR scales that by hover efficiency and RPM headroom, so it equals TWR for a motor at 8 g/W and 10,000 RPM. Full methodology and the whole catalogue →