Following are the steps which you might need to follow
Step 1: Connect your Raptor 2.1 to the FOCBOX UI App using Bluetooth or USB
Step 2: Goto the "HUD" tab and click the Gear Icon.
Step 3: Change the value written in front of Test ERPM -> RPM to 10 if it's above or below it.
Step 4: Click OK and throttle check your board.
Note: 30 MPH = 48.28 KM/H