SEEKR2 supports hydrogen mass repartitioning (HMR), allowing one to use a timestep of up to 4 fs. HMR works by repartitioning some of the mass of a heavy atom bonded to a hydrogen onto the hydrogen atom, enabling one to use a larger timestep without causing numerical instability in the simulation. Theory shows that HMR correctly produces thermodynamic quantities; however, its effect on kinetics quantities is unclear. We show in a later section that HMR produces reasonable kinetic results for systems within SEEKR2.