A work vehicle comprising an engine , an air filtration system configured to filter air provided to the engine and comprising an air filter pre-cleaner , an aspiration system to remove particles from the air filter pre-cleaner of the work vehicle , the aspiration system comprising: an exhaust tube extending along a flow direction from an upstream end to a downstream end , the exhaust tube defining an exhaust passage extending from the upstream end of the exhaust tube to the downstream end of the exhaust tube , wherein the downstream end of the exhaust tube is open to the atmosphere, the exhaust tube including a venturi portion , the exhaust tube further having an aperture within the venturi portion of the exhaust tube ; and an aspiration tube configured to be coupled between the exhaust tube and the air filter pre-cleaner of the work vehicle , the aspiration tube defining an aspiration passage extending between the air filter pre-cleaner and the exhaust tube , the aperture through the exhaust tube fluidly coupling the aspiration passage and the exhaust passage ; characterized in that : a restrictor body positioned within the exhaust passage , the restrictor body comprising a leading edge and a trailing edge , with the leading edge being positioned upstream from the trailing edge along the flow direction and the aperture through the exhaust tube being positioned downstream of the leading edge of the restrictor body ; and the restrictor body and the venturi portion are configured to adjust a flow parameter of exhaust gases flowing through the exhaust passage , with the restrictor body configured to direct exhaust gases flowing through the exhaust passage radially outward toward the exhaust tube and the venturi portion configured to direct exhaust gases flowing through the exhaust passage radially inward toward a centre of the exhaust passage . an exhaust tube extending along a flow direction from an upstream end to a downstream end , the exhaust tube defining an exhaust passage extending from the upstream end of the exhaust tube to the downstream end of the exhaust tube , wherein the downstream end of the exhaust tube is open to the atmosphere, the exhaust tube including a venturi portion , the exhaust tube further having an aperture within the venturi portion of the exhaust tube ; and an aspiration tube configured to be coupled between the exhaust tube and the air filter pre-cleaner of the work vehicle , the aspiration tube defining an aspiration passage extending between the air filter pre-cleaner and the exhaust tube , the aperture through the exhaust tube fluidly coupling the aspiration passage and the exhaust passage ; a restrictor body positioned within the exhaust passage , the restrictor body comprising a leading edge and a trailing edge , with the leading edge being positioned upstream from the trailing edge along the flow direction and the aperture through the exhaust tube being positioned downstream of the leading edge of the restrictor body ; and the restrictor body and the venturi portion are configured to adjust a flow parameter of exhaust gases flowing through the exhaust passage , with the restrictor body configured to direct exhaust gases flowing through the exhaust passage radially outward toward the exhaust tube and the venturi portion configured to direct exhaust gases flowing through the exhaust passage radially inward toward a centre of the exhaust passage . <EOS>