To remove the evap system from the '08 250r (California models) you need to pipe off the gas tank. Simply re-use the hoses that led from the gas tank to the evap canister and simply add a cheapy fuel filter to the end . This hose will act as the tank's vent and the blue dot port is capped off.
Here's the evap system from a 2008 Ninja 250r (California model) removed. Circled in red are the two points that tie into the vacuum tee going to the gas valve, and the other is where it ties into the clean air system. The other two connection points are at the gas tank and are not circled as they'v