10 Best Bicycle Engine Kits 2025 in the United States

The JJIESHENG 100cc Bicycle Engine Kit is a 2-stroke motor designed to add power and speed to standard bicycles, reaching a top speed of about 28 mph. Its 100cc engine size is a solid choice for boosting a bike’s performance without being overly complex. A notable strength is its large 0.53-gallon fuel tank, which supports longer rides with fewer refuels—about 0.66 gallons per 100 km, which is fairly efficient for a gas-powered bike motor. The kit is built to handle a weight load up to 440 pounds, making it suitable for most riders and their gear.

Durability is another plus, thanks to its aluminum engine body and iron fuel tank and chain, all treated with protective finishes to ensure long-term, stable use. The motor is compatible with 26” and 28” bikes, making it suitable for those standard sizes. It runs relatively quietly at around 75 decibels, which helps reduce noise disturbance during use. As a gas engine, it requires regular maintenance like any motor of this type, including fuel and oil care.

This kit is a good fit for cyclists wanting a reliable, moderately powerful motor upgrade to their bikes, especially if they prefer gasoline engines and value durability and decent speed.

The CUBELLIN 100cc Bike Motor Kit is a solid choice for those looking to convert their bicycle into a motorized bike. Its 4-stroke engine provides robust power with 3.5HP and a max speed of 50km/h, making it suitable for various terrains including mountain and road biking. Its air-cooling system and overhead valve technology enhance fuel efficiency and longevity, consuming just 0.66 gallons per 100km.

The kit's durability is notable, with an aluminum engine shell and iron fuel tank, ensuring a high max bearing capacity of 440 pounds. The package includes all necessary components for conversion, which could be complex for beginners but manageable for those with some mechanical skill. It is designed to fit bikes with large triangular empty frames, adding versatility in compatibility.

The product does require assembly, and its skill level is marked as advanced, which might deter newcomers. Additionally, while the noise level is relatively low at 75dB, it is still audible and might not be suited for noise-sensitive areas. The engine's size and weight could also affect the bike's balance and handling. This kit is particularly beneficial for experienced cyclists or hobbyists looking to upgrade their bike's performance and efficiency.

The Upyouths 100CC Bicycle Engine Kit is designed to convert a standard bicycle into a motorized one, using a 4-stroke gas engine. This kit's 100cc engine offers a good balance of power and efficiency, which is suitable for commuting and short rides. The 4-stroke engine is quieter and more reliable than a 2-stroke engine, providing smoother performance. With a maximum speed of 3600rpm, it ensures a decent pace for urban travel.

The materials used – aluminum, iron, and plastic – promise durability and wear resistance, which contribute to the engine’s longevity. The 1.6L fuel tank capacity and a reasonable fuel consumption rate mean fewer refueling stops and economical running costs. However, the installation complexity can be a significant hurdle for those without technical skills, as professional installation is recommended. Additionally, the kit’s compatibility with various bicycle types may require careful consideration and possibly some adjustments.

The included components are comprehensive, covering all necessary parts for the conversion. Its weight of over 46 pounds can be a downside, potentially affecting the bicycle’s handling and balance. This engine kit is best suited for hobbyists and enthusiasts who are comfortable with mechanical tasks or have access to professional installation services.