The UMS 3-Cylinder 100cc Petrol Radial Engine delivers classic radial appearance, distinctive 3-cylinder sound, and dependable 4-stroke performance. Compact yet powerful, it’s ideal for scale warbirds and vintage aircraft requiring authentic aesthetics and smooth operation.

Product Description

The UMS 3-100cc Radial Engine is a precision-built 4-stroke petrol powerplant designed for scale aircraft enthusiasts seeking the perfect blend of realism, performance, and durability. Its traditional 3-cylinder radial configuration provides an unmistakable vintage appearance and sound, making it ideal for detailed warbirds, golden-era aircraft, and custom scale projects.

With a 100cc displacement, this engine offers strong, reliable power in a manageable size, making it suitable for a wide range of mid-size scale aircraft applications.

Supplied ready to run, the engine includes:

• Exhaust collector ring

• Electronic ignition system

• Spark plugs

• Durable engine mount

Integrated choke and throttle bellcranks simplify installation and ensure smooth throttle response, allowing for straightforward setup and precise control.

Manufactured using CNC-machined aluminium and bar stock components, the engine maintains strict tolerances for consistent reliability. The aircraft-grade alloy cylinder heads and crankcases provide strength while optimising weight distribution for stable flight performance.

Internally engineered for long service life, the engine features:

• Heavy-duty double-bearing crankshaft for stable high-RPM operation

• Billet aluminium pistons with hardened steel rings

• Hard-chromed and lapped cylinder bores for reduced wear

• Hardened steel camshafts for accurate and durable valve timing

Designed to run on 87–110 octane petrol with a 32:1 fuel-to-oil mixture, the UMS 3-100cc radial offers smooth ignition, strong torque, and dependable operation.

Whether you're building a detailed warbird replica or a custom radial-powered project, this engine delivers authentic character, refined engineering, and proven reliability.

Key Features

• 3-cylinder 4-stroke petrol radial engine

• 100cc displacement

• Authentic radial appearance and distinctive sound

• Ready-to-run with ignition, plugs and collector ring

• CNC-machined aluminium and bar stock construction

• Aircraft-grade alloy heads and crankcases

• Double-bearing crankshaft for durability

• Billet pistons with hardened steel rings

• Hard-chromed cylinder bores for enhanced longevity

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

Perfect For

• Scale RC warbirds

• Golden-era and vintage aircraft replicas

• Custom radial-powered builds

• Competition scale aircraft

• Experienced hobbyists and professional builders

Specifications

Engine Type: 4-Stroke
Cylinders: 3 (ABC Type)
Displacement: 100cc
Bore: 37mm
Stroke: 32mm
Approx. Thrust: 13.5kgf
RPM Range: 1,000 – 5,500
Weight (with silencer & ignition): Approx. 3.8kg
Engine Diameter: 255mm
Engine Length: 185mm
Recommended Propellers:

• 2-Blade 24×10

• 2-Blade 28×8
  

Muffler Type: Collector Ring
Spark Plug: CM-6
Carburettor: Walbro
Fuel Type: Petrol (87–110 octane, 32:1 mix)

Why Buy from Probuild Aircraft

✅ Official UK stockist – 100% genuine UMS engines
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✅ Fast UK shipping and secure packaging
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