Boot up MotoGP and select "Load Game" from the main menu. Quick Troubleshooting

Transfer between PSPs, Memory Sticks, and PC

PSP does not have a trophy system. So, no issues—you can safely use any save.

B. Restore save from PC to PSP

On both a physical PSP and the PPSSPP emulator, save files are stored in a specific folder structure: [Memory Stick Root] -> PSP -> SAVEDATA

Place the folder in Documents/PPSSPP/PSP/SAVEDATA/ .