RETROL HM-01 7cc Hit and Miss Engine Model 4-Stroke Horizontal Stationary Gas Motor with Speed Gear
Hero Section: A Tribute to the Golden Age of Agriculture
The RETROL HM-01 is not just a model; it is a labor of love. Developed over four months by the RETROL team, this "Racing Red" 7cc engine captures the soul of the horizontal stationary engines that powered 20th-century farms. Cast from heavy-duty 304 Stainless Steel, it combines rugged industrial durability with the elegance of kinetic art. Whether you are a veteran collector or a mechanical novice, the HM-01 offers a unique auditory and visual experience—the iconic POP... whoosh... whoosh rhythm of the Hit & Miss cycle, brought to life on your desktop.
Why Choose the RETROL HM-01?
- Exclusive "Fast-Slow" Switch Gear: This is a game-changer. Unlike standard engines that run at a fixed pace, the HM-01 features a specially designed gear mechanism. You can switch between "High Speed" for power output and "Super-Slow" for a mesmerizing, tick-over idle display. It dramatically increases the playability of the engine.
- Premium 304 Stainless Steel Casting: While other models use softer alloys, the HM-01 uses cast 304 Stainless Steel for the main body, flywheel, and connecting rods. The crankshaft is high-carbon steel, hardened for durability. This ensures the engine is rust-resistant, heavy, and built to last generations.
- Authentic Visual Details: Finished in a classic electrophoretic "Agricultural Red," it looks like it was pulled straight from a vintage tractor. The visible, adjustable-flow brass oil cup and the resonance exhaust pipe add layers of mechanical realism.
- A Builder’s Dream: This engine is the perfect heart for your custom project. Since it requires a base and ignition system (sold separately), it gives you the freedom to mount it on custom wood, integrate it into a diorama, or belt-drive miniature machinery.
Technical Highlights: Engineering Insight
- Hit & Miss Governor: The engine uses a centrifugal governor to control speed. When the RPM rises, the exhaust valve stays open (Miss), allowing the engine to coast. When it slows, it fires (Hit). This cycle is clearly visible and audibly distinct.
- Evaporative Cooling: Features a true water hopper for evaporative cooling, requiring water top-ups during long runs, just like the real engines of the 1900s.
- Precision CNC Machining: All assembly surfaces are CNC processed to ensure high airtightness and smooth operation right out of the box.
Specifications
- Brand: RETROL
- Model: HM-01
- Displacement: 7cc
- Type: Horizontal Single-Cylinder 4-Stroke Hit & Miss
- Material: 304 Stainless Steel (Body/Flywheel), High-Carbon Steel (Crankshaft)
- Bore: 20mm
- Stroke: 22mm
- Cooling: Evaporative Water Cooling
- Lubrication: Mixed Oil + Adjustable Oil Cup
- Dimensions: 17 x 13 x 13cm
- Weight: 1800g
Usage Scenario: The Custom Project
You receive the heavy box. Inside lies the gleaming red HM-01. You spend the weekend crafting a custom oak base, mounting the fuel tank, and wiring up the ignition module. You fill the oil cup and the water hopper. You flip the flywheel. The engine comes alive—a slow, rhythmic heartbeat. You flip the "Fast-Slow" gear, and the rhythm changes. This isn't a toy you bought; it's a machine you commissioned.
Important Tips from the Expert
- What You Need (Not Included): Please note this is the Engine Unit Only. To run this engine, you will likely need to source or build: A Wooden Base, Fuel Tank, Fuel Line, Spark Plug (1/4-32 ME8), and a CDI Igniter.
- Lubrication: This engine uses a mix of methods. You must mix 2T Oil with Gasoline (Ratio 1:25) for the fuel. Additionally, fill the visible brass oil cup to lubricate the piston/cylinder.
- Cooling: Never run the engine without water in the cooling hopper.
Customer Support
Building a setup for a standalone engine requires skill. If you need advice on compatible ignition modules or spark plugs, our team is here to guide you: service@helloworld7.com
Delivery
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