Review on Unleash Your Ruckus 50's Potential with NCY 0900-1076 Performance CDI - No Rev Limiter by Philip Anderson

If you are using a newer Ruckus that has the limiter set to 8900 instead of 8000 then you are almost certainly downgrading unless you have a lot of mods on your scooter Installed. My mods: Polini variator and 5.5g roller belt (mass upgrade) Iridium spark plugs K&N intake manifold with injector (77) is a bit trickier. If you're looking to upgrade the engine quickly or want to exit and get your motorcycle license it might be worth removing the airbox, upgrading the carburetor and upgrading the exhaust, but honestly this is a 49cc scooter. See why bother so. Upgrade the engine to GY6 if you need speed.