Here is a proven collection of parts, to get your bike up to speed. Includes: Polini belt Clutch spring kit Polini variator 9:1, or 9:8:1 gears Malossi CDI These components will only compliment the Big bore kit you decide to add later. These parts alone will get you close to, or over 50mph on an otherwise stock DIO SR. This is a great first step to get your bike to higher speeds, with only touching the transmission. This DOES NOT require any jetting, or engine tuning.