Joined: May 2013
Posts: 202
Likes: 19
From: Salt Lake City, UT, USA
Bikes: 2011 Raleigh Sojourn, 2012 Marin Four Corners, 2013 Soma Saga, 2014 Scott Spark 940, 2017 Brompton H6E, 2016 Trek FX 7.2
IIRC, the RX bags will fit on RX and MTX racks, but the MTX bags will only fit on MTX racks. This is to allow use of any bag (RX or MTX) on the heavier duty line of racks (MTX), but to disallow use of heavier duty bags on the lighter duty RX racks as to prevent overloading to the point of failure.