CDI BOX compatible with: BLACKBOX CDI Ignition Rev Box Yamaha YZ250 YZ 250 2002 - 2005. CDI BOX instructs the fuel injectors when and for how long they should spray. It also directs the spark plugs on how to perform especially when they have to fire. When a CDI box is bad, it can lead to misfires, issues with starting, rough running or even stall the motor.
