The UMS 5-Cylinder 260cc Petrol Radial Engine is a premium 4-stroke powerplant designed for scale aircraft builders who demand authentic radial appearance, smooth operation, and dependable performance. With its classic 5-cylinder layout, precision CNC construction, and ready-to-run configuration, this engine delivers realistic sound, excellent torque, and long-term reliability for serious RC and scale aviation projects.

Product Description

The UMS 5-Cylinder 260cc Radial Engine blends traditional radial engine aesthetics with modern engineering to create a powerful and reliable propulsion solution for large-scale model aircraft. Its 5-cylinder radial configuration provides a striking, realistic appearance while ensuring smooth, balanced running across the RPM range.

With a 260cc displacement, this engine is ideally suited for scale warbirds, vintage aircraft, and precision-built projects that require both visual authenticity and strong performance. Supplied ready to run, it includes an exhaust collector ring, electronic ignition system, spark plugs, and a robust engine mount making installation straightforward and hassle-free.

Manufactured using precision CNC-machined aluminium and bar stock, the engine features aircraft-grade alloy cylinder heads and crankcases, delivering exceptional strength without unnecessary weight. Internally, durability and smoothness are ensured by a heavy-duty double-bearing crankshaft, billet aluminium pistons with hardened steel rings, and hard-chromed, lapped cylinder bores for excellent wear resistance and compression retention.

Hardened steel camshafts provide accurate valve timing and long service life, while integrated choke and throttle bellcranks make setup and operation simple. Designed to run on 87–110 octane petrol with a 32:1 fuel-to-oil mixture, the UMS 5-260cc radial engine offers versatility, efficiency, and proven reliability.

This engine is an outstanding choice for builders seeking authentic radial sound, refined engineering, and dependable 4-stroke performance.

Key Features

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

• 260cc displacement delivering smooth torque and reliable power

• Ready-to-run package including ignition, plugs, exhaust 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 piston rings

• Hard-chromed and lapped cylinder bores for durability

• Hardened steel camshafts for precise valve timing

• Integrated choke and throttle bellcranks for easy installation

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

Perfect For

• Large-scale RC warbirds and vintage aircraft

• Scale and competition-grade aircraft builds

• Builders seeking realistic radial engine sound and appearance

• Smooth, reliable 4-stroke power applications

• Advanced hobbyists and professional aircraft modellers

Specifications

Engine Type: 4-Stroke
Cylinders: 5 (ABC Type)
Displacement: 260cc
Bore: 40mm
Stroke: 42mm
Approx. Thrust: 27kgf @ 33×14 prop
RPM Range: 1,000 – 5,500
Weight (with silencer & ignition): Approx. 6.0kg
Engine Diameter: 286mm
Engine Length: 208mm
Recommended Propellers:

• 2-Blade 32×12

• 2-Blade 32×14

• 2-Blade 33×14

Muffler Type: Collector Ring
Spark Plug: CM6
Carburettor: Walbro
Fuel Type: Petrol (87–110 octane, 32:1 mix)

Why Buy from Probuild Aircraft

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