The UMS 5-Cylinder 75cc Petrol Radial Engine delivers authentic radial sound, realistic scale appearance, and smooth 4-stroke performance in a compact, lightweight package. Supplied ready to run, it is the ideal powerplant for smaller scale warbirds and vintage aircraft requiring dependable petrol radial performance.

Product Description

The UMS 5-Cylinder 75cc Radial Engine combines classic radial realism with modern precision engineering. Designed specifically for scale aircraft builders, this 4-stroke petrol engine offers the distinctive sound, appearance, and smooth power delivery associated with full-size radial aircraft engines.

With a 75cc displacement, this engine is perfectly suited to smaller scale warbirds, vintage models, and detailed replica builds where weight, balance, and authenticity matter. Delivered ready to run, it includes an exhaust collector ring, spark plugs, electronic ignition system, and engine mount for straightforward installation and reliable starting.

All major components are precision CNC-machined from aluminium or bar stock, ensuring consistent manufacturing tolerances and dependable performance. The aircraft-grade alloy cylinder heads and crankcases provide excellent strength-to-weight ratio and thermal stability during operation.

A heavy-duty double-bearing crankshaft ensures smooth, vibration-controlled performance and long service life. Internally, billet aluminium pistons fitted with hardened steel rings operate within hard-chromed and lapped cylinder bores, reducing friction and enhancing durability. Hardened steel camshafts provide precise valve timing and long-term reliability.

Designed to operate on 87–110 octane petrol with a 32:1 fuel-to-oil mixture, this compact radial engine offers flexibility, efficiency, and dependable power for scale aviation enthusiasts seeking true radial character.

Key Features

• 5-cylinder 4-stroke radial engine with authentic scale appearance

• 75cc displacement ideal for smaller scale aircraft

• Supplied ready to run with ignition, plugs, collector ring & engine mount

• Precision CNC-machined aluminium and bar stock construction

• Aircraft-grade alloy cylinder heads and crankcases

• Heavy-duty double-bearing crankshaft for smooth operation

• Billet aluminium pistons with hardened steel rings

• Hard-chromed and lapped cylinder bores for durability

• Hardened steel camshafts for reliable valve timing

• Integrated choke and throttle bellcranks for easy setup

• Compatible with 87–110 octane petrol (32:1 mix)

Perfect For

• Smaller scale RC warbirds

• Vintage and classic aircraft builds

• Lightweight radial engine applications

• Builders seeking realistic radial sound

• Advanced hobbyists and precision modellers

Specifications

Engine Type: 4-Stroke
Cylinders: 5 (ABC Type)
Displacement: 75cc
Bore: 26.5mm
Stroke: 27.5mm
Approx. Thrust: 9kgf @ 24×8 prop
RPM Range: 1,000 – 6,000
Weight (with silencer & ignition): Approx. 3.0kg
Engine Diameter: 230mm
Engine Length: 162mm
Recommended Propellers:

• 2-Blade 24×8

• 2-Blade 24×10
  

Muffler Type: Collector Ring
Spark Plug: 1/4-32
Carburettor: Walbro
Fuel Type: Petrol (87–110 octane, 32:1 mix)

Why Buy from Probuild Aircraft

✅ Official UK stockist – 100% genuine UMS engines
✅ Trusted by top international pilots and builders
✅ Fast UK shipping and secure packaging
✅ Supplying and supporting pilots since 1993

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