Transmission and method for shifting gears

A transmission comprising:

• an input shaft configured for operatively connecting to a motor;
• an input gear connected to the input shaft, the input gear being drivingly engaged to the input shaft;
• a shaft;
• a drive gear connected to the shaft, the drive gear selectively rotating relative to the shaft, and the drive gear drivingly engaging the input gear;
• a dog gear connected to the shaft, the dog gear drivingly engaging the shaft, and the dog gear selectively axially translating along the shaft between:
• an engaged dog position in which the dog gear is drivingly engaged with the drive gear such that the dog gear rotates together with the drive gear;
• and
• a disengaged dog position in which the dog gear is disengaged from the drive gear,
• an output gear connected to the shaft, the output gear drivingly engaging the shaft;
• a shifting assembly including:
• a shift drum selectively rotating about a shift drum axis between a first drum position and a second drum position;
• a retainer connected to the shift drum, the retainer selectively moving between a retracted position and an extended position;
• a retainer biasing member biasing the retainer toward the extended position;
• a shift fork engaging the shift drum and operatively connected to the dog gear, the shift fork selectively moving between an engaged fork position and a disengaged fork position,
• with the shift fork in the engaged fork position, the shift drum is in the first drum position;
• and
• with the shift fork in the disengaged fork position, the shift drum is in the second drum position;
• a shift fork biasing member biasing the shift fork toward the engaged fork position;
• the shifting assembly having:
• a drive configuration in which:
• the shift drum is in the first drum position;
• the shift fork is in the engaged fork position, such that the dog gear is in the engaged dog position;
• and
• the retainer is in the extended position, and prevents the shift fork from moving toward the disengaged fork position,
• a neutral configuration in which:
• the shift drum is in the second drum position;
• the shift fork is in the disengaged fork position, such that the dog gear is in the disengaged dog position;
• and
• the retainer permits the shift fork to move between the disengaged fork position and the engaged fork position,
• in response to the shift drum rotating from the second drum position toward the first drum position, the shift fork moves from the disengaged fork position toward the engaged fork position, and the shift fork causes the dog gear to move toward the engaged dog position.