Stirlingkit User Guide

Thank you to every builder who has run an HM-01 and taken the time to share feedback with us. Many of you told us what could be easier, from mounting the flywheels to finding the right battery for the ignition. We listened, worked with RETROL, and decided to update the...

Looking to pick up your very first hit and miss engine? With RETROL and OKMO offering two popular horizontal four-stroke models priced within $30 of each other, many hobbyists find themselves stuck on which one to choose. It really comes down to your hands-on preference: if you love the challenge...

Are you tired of your engine firing up only to immediately force your connected water pumps or retro generators into a wild frenzy, leaving you no way to let it idle smoothly on its own without dragging your entire setup along? That is exactly what the P51 Friction Clutch Pulley...

We have recently received feedback from some customers regarding the performance of the HM-01 CDI system. To ensure transparency and help you resolve any issues quickly, we would like to provide a clear explanation along with our current solutions.   🔧 HM-01 Starting Issue Troubleshooting Guide If you are experiencing...

The Retrol HM01 is a 7cc, horizontal single-cylinder, four-stroke Hit & Miss engine designed for hobbyists and collectors. It features a 20mm cylinder diameter and 22mm stroke, uses an evaporative water-cooling system, and is lubricated with mixed oil via an oil cup (recommended gasoline-oil ratio 1:25). The engine starts manually...

What is the Musa hm01 engine known for in terms of design? Answer: The Musa hm01 engine is known for its meticulous design, high-quality craftsmanship, and attention to detail.   How does the Musa hm01 compare to other hit and miss engines in terms of quality?   Answer: According to...