10 Best Bicycle Engine Kits 2026 in the United States

This 100cc 4-stroke gasoline bicycle engine kit offers solid power with 3.5 horsepower, allowing speeds up to around 50 km/h, which makes it a good choice for riders wanting a noticeable boost without going full motorcycle. Its air-cooled OHV (overhead valve) engine design helps reduce fuel consumption and carbon buildup, making it more economical and reliable over time. The kit includes a large 0.52-gallon fuel tank, so you won't need to refuel frequently during rides. Durability is a strong point here, thanks to corrosion-resistant materials like aluminum and steel, plus a robust chain and belt system designed to handle up to 440 pounds, suitable for heavier frames.

Noise levels are moderate, about 75dB, so it won’t be completely silent but should be acceptable for outdoor use. Installation might require some mechanical skill since it’s intended for large triangular bicycle frames or motorized bike modifications, and compatibility depends on your bike’s frame size and setup. This makes it a great budget-friendly option for those wanting to convert a bicycle into a motorized bike without investing in a full motorcycle.

It may not be the best fit if you need a simpler plug-and-play system or if your bike frame is smaller or uniquely shaped. Also, while maintenance is relatively straightforward due to the 4-stroke engine design, some familiarity with engine upkeep will be helpful to keep it running smoothly.

This 100cc bicycle engine kit is a solid choice for anyone wanting to motorize their mountain, road, gravel, or beach bike. It features a 4-stroke gasoline engine with a 100cc displacement, providing a respectable 3.5 horsepower and a top speed around 50 km/h, which is enough power for casual commuting or leisurely rides. The air-cooled design and double belt drive add to reliable performance and smoother operation.

Durability is a strong point here, with an aluminum engine shell, iron fuel tank, and rust-resistant steel chain that can handle up to 440 pounds, making it sturdy for different bike types and terrains. Its 0.52-gallon fuel tank and efficient fuel consumption (about 0.66 gallons per 100 km) mean fewer stops for refueling and cost savings over time. The engine runs quietly at around 75 dB, so it won’t cause much noise disturbance.

This engine kit suits riders who want a durable, powerful, and fuel-efficient upgrade for their bike and are comfortable with a bit of DIY assembly or have access to help. It is less ideal for those seeking plug-and-play ease or guaranteed service support.

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.