2019 American Chemical Society. A series of metal-organic frameworks (MOFs) (PCN-606-OH-TPDC, PCN-606-OMe-TPDC, PCN-606-OH-EDDB, and PCN-606-OMe-EDDB) are synthesized through linker installation onto open sites of 8-connected Zr6 clusters in PCN-606-R (where R = -OH or -OMe) parent frameworks of differing flexibilities. The two postsynthetically installed linear linkers possess slight differences in length and bulk, which result in a noticeable difference in the installation temperatures, reflective of a different thermodynamic barrier to incorporation into PCN-606-R. The X-ray crystallographic data as well as the N2 adsorption properties of these four newly produced MOFs are explored and compared to gain a more comprehensive understanding of the implications that this difference in linker size and bulk have during insertion into flexible MOFs.