Original sentence: Even though the fan's physical appearance remained unchanged, the manufacturer has chosen a weaker motor in the most recent revision (2002-Present); (the motor, though still oil-lubricated, was switched to a skeletal design; see details on skeletal motors below)
Edited sentence: Sadly, even though the fan's physical appearance remained unchanged, the motor was further downgraded in 2002 when production was shipped overseas; (the motor, though still oil-lubricated, was switched to a skeletal design; see details on skeletal motors below)