BikeBerry.com has every single part you need to repair and upgrade your 2-stroke bicycle engine’s drivetrain. If your 2-stroke motorized bicycle’s chain or rear sprocket is in worn out and in need of replacement, we’ve got you covered with the parts and tools you need to get the job done. If you want to upgrade your motorized bike’s torque with a bigger sprocket or its speed with a Jackshaft kit, we’ve got parts from BBR Tuning that’ll have you riding the way you want in no time.