When checking the engine oil level on a motorcycle, what does a level above the upper limit mark on the dipstick indicate or cause?

1. Excess oil can be whipped into foam by the crankshaft, leading to poor lubrication and oil leaks through the breather hose.
2. It is a recommended practice to provide extra lubrication for high-speed riding.
3. The oil pressure will drop to zero because the oil pump becomes submerged.
4. It indicates that the fuel tank is leaking into the oil sump through the carburetor vent.