If you're looking for small motorcycles with big engines, similar to the power and presence of a Harley-Davidson, there are several options available from various motorcycle manufacturers. Here are a few examples:
Ducati Diavel: The Ducati Diavel is a cruiser-style motorcycle with a muscular design and a powerful engine. It features a large displacement engine and offers a combination of performance and style.
Triumph Rocket 3: The Triumph Rocket 3 is a heavyweight cruiser that boasts a massive 2,500cc engine, making it one of the most powerful production motorcycles on the market. It offers a unique blend of power, comfort, and style.
Indian Scout: The Indian Scout is a mid-sized cruiser motorcycle with a classic design and a powerful engine. While not as large as some of the heavyweight Harley-Davidson models, it provides a good balance between power and maneuverability.
Yamaha VMAX: The Yamaha VMAX is a muscle cruiser with a distinctive look and a powerful engine. It features a 1,679cc V4 engine that delivers impressive acceleration and performance.
Kawasaki Vulcan 1700: The Kawasaki Vulcan 1700 series includes models such as the Voyager, Vaquero, and Nomad. These cruisers offer a substantial engine displacement and a comfortable riding experience.
Remember that the definition of a "big engine" may vary, and it's important to consider factors such as your riding preferences, intended use, and budget when choosing a motorcycle. It's always recommended to visit local dealerships, test ride the motorcycles, and find the one that suits your needs and riding style the best.