An actuation mechanism for a surgical clip applier, the actuation mechanism comprising: a drive bar movable through a stroke length having a first portion and a second portion to fire at least one surgical clip, the drive bar defining an output gear rack; a trigger pivotable from an un-actuated position to an actuated position; a first intermediate gear, which is a compound gear including an arcuate input portion and an arcuate output portion, the arcuate input portion operably coupled to the trigger such that pivoting of the trigger from the un-actuated position to the actuated position rotates the first intermediate gear; and a second intermediate gear, which is a compound gear including an arcuate input portion and an arcuate output portion, the arcuate input portion of the second intermediate gear operably coupled to the trigger such that pivoting of the trigger from the un-actuated position to the actuated position rotates the second intermediate gear, wherein in the first portion of the stroke length, the arcuate output portion of the first intermediate gear is disposed in meshed engagement with the output gear rack and the arcuate output portion of the second intermediate gear is disengaged from the output gear rack such that the first intermediate gear drives the drive bar along the first portion of the stroke length in response to pivoting of the trigger; in the second portion of the stroke length, the output portion of the second intermediate gear is disposed in meshed engagement with the output gear rack and the output portion of the first intermediate gear is disengaged from the output gear rack such that the second intermediate gear drives the drive bar along the second portion of the stroke length in response to pivoting of the trigger; and the output portions (157b, 159b) of the first and second intermediate gears (156, 158) define different diameters ("Di", "D 2 "), and a different mechanical advantage is provided in the first portion of the stroke length as compared to the second portion of the stroke length. a drive bar movable through a stroke length having a first portion and a second portion to fire at least one surgical clip, the drive bar defining an output gear rack; a trigger pivotable from an un-actuated position to an actuated position; a first intermediate gear, which is a compound gear including an arcuate input portion and an arcuate output portion, the arcuate input portion operably coupled to the trigger such that pivoting of the trigger from the un-actuated position to the actuated position rotates the first intermediate gear; and a second intermediate gear, which is a compound gear including an arcuate input portion and an arcuate output portion, the arcuate input portion of the second intermediate gear operably coupled to the trigger such that pivoting of the trigger from the un-actuated position to the actuated position rotates the second intermediate gear, wherein in the first portion of the stroke length, the arcuate output portion of the first intermediate gear is disposed in meshed engagement with the output gear rack and the arcuate output portion of the second intermediate gear is disengaged from the output gear rack such that the first intermediate gear drives the drive bar along the first portion of the stroke length in response to pivoting of the trigger; in the second portion of the stroke length, the output portion of the second intermediate gear is disposed in meshed engagement with the output gear rack and the output portion of the first intermediate gear is disengaged from the output gear rack such that the second intermediate gear drives the drive bar along the second portion of the stroke length in response to pivoting of the trigger; and the output portions (157b, 159b) of the first and second intermediate gears (156, 158) define different diameters ("Di", "D 2 "), and a different mechanical advantage is provided in the first portion of the stroke length as compared to the second portion of the stroke length.