A draper platform for mounting on a feederhouse of an agricultural combine, the draper platform having a forward direction of operational travel over the ground and an overall width in a direction transverse to the forward direction, the draper platform comprising: a frame (102, 104, 106), wherein said frame (102, 104, 106) is elongate and extends generally perpendicularly to the forward direction and extends generally parallel to the ground; a plurality of reciprocating knife support arms that extend in the forward direction and are pivotally coupled at the rear of the plurality of support arms to the frame (102, 104, 106), to pivot generally up and down at their forward ends about their pivotal connections to the frame (102, 104, 106) and with respect to the frame (102, 104, 106); a reciprocating knife assembly that is elongate and extends laterally across substantially the entire overall width of the draper platform, wherein said reciprocating knife assembly is disposed at a forward edge of the draper platform, wherein said reciprocating knife assembly is connected to and supported on forward ends of the plurality of support arms, wherein the reciprocating knife assembly is configured to flex and to thereby permit each support arm of the plurality of support arms to independently pivot up and down with respect to the forward ends of adjacent ones of the plurality of support arms; and a reciprocating knife drive comprising a sub-frame and a first pivoting drive member having a front end and a rear end, the first pivoting drive member being supported on the sub-frame at a first pivot to pivot with respect to the sub-frame about a first generally vertical axis; characterised in that the sub-frame is disposed between and supported on two adjacent support arms of said plurality of support arms. a frame (102, 104, 106), wherein said frame (102, 104, 106) is elongate and extends generally perpendicularly to the forward direction and extends generally parallel to the ground; a plurality of reciprocating knife support arms that extend in the forward direction and are pivotally coupled at the rear of the plurality of support arms to the frame (102, 104, 106), to pivot generally up and down at their forward ends about their pivotal connections to the frame (102, 104, 106) and with respect to the frame (102, 104, 106); a reciprocating knife assembly that is elongate and extends laterally across substantially the entire overall width of the draper platform, wherein said reciprocating knife assembly is disposed at a forward edge of the draper platform, wherein said reciprocating knife assembly is connected to and supported on forward ends of the plurality of support arms, wherein the reciprocating knife assembly is configured to flex and to thereby permit each support arm of the plurality of support arms to independently pivot up and down with respect to the forward ends of adjacent ones of the plurality of support arms; and a reciprocating knife drive comprising a sub-frame and a first pivoting drive member having a front end and a rear end, the first pivoting drive member being supported on the sub-frame at a first pivot to pivot with respect to the sub-frame about a first generally vertical axis; characterised in that the sub-frame is disposed between and supported on two adjacent support arms of said plurality of support arms.