Broken Chain Guide?

[noahg]

I have disassembled the engine up until the actual block. That's what the attached image is. I'm wondering if that hole is suppose to be there? I doubt it though because I see small metal pieces around it. The piston head, rod, and rings are all fine. The sound that it was making sounded like the rod or the piston head was broken but they are in reletively good shape. Is there a way to take the actual block apart without destroying everything? Sometimes I have to go full throttle when my scooters top speed is 45mph... I'm just hoping I can fix it since I've already put like 150-200$ into fixing it already. Thanks for the reply though.