Robin-Subaru: Professional Power. Rugged Reliability.
From industrial job sites to rural properties, Robin-Subaru Engines set the bar for cutting-edge performance. Designed for maximum durability and quiet operation. Whether you’re upgrading to a new unit or sourcing precision spares for maintenance, we have the gear and the expertise to keep you moving.
Experience the durability of Robin-Subaru.
The Robin EX27 (often marketed under Robin-Subaru) is a heavy-duty, commercial-grade 9.0-horsepower petrol engine. Stepping up in displacement from the EX21, the EX27 is engineered to provide high-output power, exceptional torque, and reliability for demanding industrial, construction, and agricultural equipment.
Key Technical Specifications
Engine Type: Air-cooled, 4-cycle, single-cylinder, Chain-Driven Overhead Cam (OHC), horizontal PTO shaft
Displacement: 265 cc
Maximum Output: 9.0 HP (6.6 kW) at 4,000 RPM
Maximum Torque: 18.6 to 18.7 Nm (approx. 13.7 ft-lbs) at 2,500 RPM
Fuel Tank Capacity: 6.1 Liters (approx. 1.6 US gallons)
Oil Capacity: 1.0 Liter (34 oz.)
Dry Weight: Approx. 21 kg (46 lbs)
Starting System: Available in standard recoil start or electric start configurations
Standout Features & Benefits
Chain-Driven OHC Design: The overhead cam configuration optimizes valve timing and combustion efficiency, resulting in lower fuel consumption and cleaner emissions compared to legacy side-valve engines.
Industrial Durability: Features a robust cast-iron cylinder sleeve, a dual ball-bearing-supported forged steel crankshaft, and a high-grade aluminum block built to withstand high loads and prolonged run times.
High Torque Curve: Delivers strong pulling power at lower RPMs (peaking at 2,500 RPM), making it ideal for machinery that encounters sudden heavy loads.
Refined Acoustics & Balance: Precision engineering reduces engine vibration significantly, while a large-capacity, soft-tone muffler keeps operational noise levels down.
Common Applications
Because of its heavy-duty output and dependable performance under stress, the EX27 is widely used for:
Log splitters and commercial wood chippers
Large pressure washers and trash water pumps
Medium-to-large portable generators
Go-karts and specialized turf/agricultural machinery
Concrete saws and heavy plate compactors
The Robin EX40 (often recognised as Robin-Subaru) is a powerhouse within the EX series, representing a heavy-duty, commercial-grade 14.0-horsepower petrol engine. Designed for the most demanding industrial, construction, and agricultural tasks, it steps up displacement and torque significantly from the EX27, serving as a reliable alternative to larger V-twin engines while maintaining a compact, single-cylinder footprint.
Key Technical Specifications
Engine Type: Air-cooled, 4-cycle, single-cylinder, Chain-Driven Overhead Cam (OHC), horizontal PTO shaft
Displacement: 404 cc
Maximum Output: 14.0 HP (10.3 kW) at 4,000 RPM
Maximum Torque: 28.5 Nm (approx. 21.0 ft-lbs) at 2,500 RPM
Fuel Tank Capacity: 7.0 Liters (approx. 1.85 US gallons)
Oil Capacity: 1.2 Liters (approx. 40 oz.)
Dry Weight: Approx. 33 kg (73 lbs)
Starting System: Typically configured with a reliable recoil start and an optional electric start setup
Standout Features & Benefits
High-Torque Performance: The 404 cc displacement combined with the OHC design delivers massive pulling power at lower RPMs, preventing the engine from bogging down under sudden, heavy shock loads.
Heavy-Duty Construction: Features a robust cast-iron cylinder sleeve, high-strength forged steel crankshaft supported by dual ball bearings, and heavy-duty crankcase covers engineered for long commercial life cycles.
Advanced OHC Cooling & Efficiency: The chain-driven overhead cam design optimizes the combustion chamber shape for better fuel efficiency, cleaner emissions, and reduced thermal stress.
Reduced Vibration and Noise: Despite its high output, the EX40 utilizes precision counter-balancing and a large-capacity muffler to keep vibrations low and operational noise comfortable.
Common Applications
The high horsepower and rugged endurance of the EX40 make it a popular choice for heavy-duty machinery, including:
Large portable generators and backup power units
Commercial-grade pressure washers and industrial trash pumps
Concrete trowels, saws, and heavy-duty plate compactors
Large log splitters and wood chippers
Turf care machinery and agricultural tractors
The Robin EX21 (frequently associated with Robin-Subaru) is a heavy-duty, industrial-grade 7.0-horsepower petrol engine. Known for its robust reliability, high torque output, and overhead cam (OHC) design, the EX21 has built a stellar reputation as a premier power plant for construction equipment, generators, water pumps, and pressure washers
Key Technical Specifications
Engine Type: Air-cooled, 4-cycle, single-cylinder, Overhead Cam (OHC), horizontal PTO shaft
Displacement: 211 cc
Maximum Output: 7.0 HP (5.1 kW) at 4,000 RPM
Continuous Output: 5.0 HP (3.7 kW) at 3,600 RPM
Maximum Torque: 13.9 Nm (approx. 10.26 ft-lbs) at 2,500 RPM
Fuel Tank Capacity: 3.6 Liters (approx. 0.95 gallons)
Oil Capacity: 0.6 Litres
Dry Weight: 16 kg (35 lbs)
Standout Features & Benefits
Overhead Cam (OHC) Technology: Unlike traditional side-valve engines, the OHC layout allows for a more efficient combustion chamber, optimised valve timing, and lower fuel consumption.
Exceptional Durability: Features a cast iron cylinder liner, a robust aluminium alloy block, and dual ball-bearing-supported crankshafts designed to handle intense, continuous commercial workloads.
Low Noise & Vibration: Engineered with larger cooling fins, a rigid muffler with a soft tone quality, and precision balancing to minimise vibration and operate quietly (around 68 dB at 7 meters).
Easy and Safe Operation: Incorporates an automatic decompression system for smooth, kickback-free recoil starting, alongside safety features like a low-oil sensor shutdown.
Common Applications
Because of its reliable power delivery across a wide torque band, you will frequently find the Robin EX21 powering:
Plate compactors and concrete trowels
Industrial portable generators (e.g., up to ~3,600W units)
High-pressure water blasters and trash pumps
Agricultural and turf equipment