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We present orbital fits and dynamical masses for HIP 113201AB and HIP36985AB, two M1 + mid-M dwarf binary systems monitored as part of the SPHERESHINE survey. To robustly determine ages via gyrochronology, we undertook aphotometric monitoring campaign for HIP 113201 and for GJ 282AB, the two wide Kstar companions to HIP 36985, using the 40 cm Remote Observatory Atacama Desert(ROAD) telescope. We adopt ages of 1.2$\pm$0.1 Gyr for HIP 113201AB and750$\pm$100 Myr for HIP 36985AB. To derive dynamical masses for all componentsof these systems, we used parallel-tempering Markov Chain Monte Carlo samplingto fit a combination of radial velocity, direct imaging, and Gaia and Hipparcosastrometry. Fitting the direct imaging and radial velocity data for HIP 113201yields a primary mass of 0.54$\pm$0.03 M$_{\odot}$, fully consistent with itsM1 spectral type, and a secondary mass of 0.145$\pm$ M$_{\odot}$. The secondarymasses derived with and without including Hipparcos/Gaia data are more massivethan the 0.1 M$_{\odot}$ estimated mass from the photometry of the companion.An undetected brown dwarf companion to HIP 113201B could be a naturalexplanation for this apparent discrepancy. At an age $>$1 Gyr, a 30 M$_{Jup}$companion to HIP 113201B would make a negligible ($<$1$\%$) contribution to thesystem luminosity, but could have strong dynamical impacts. Fitting the directimaging, radial velocity, and Hipparcos/Gaia proper motion anomaly for HIP36985AB, we find a primary mass of 0.54$\pm$0.01 M$_{\odot}$ and a secondarymass of 0.185$\pm$0.001 M$_{\odot}$ which agree well with photometric estimatesof component masses, the masses estimated from $M_{K}$-- mass relationships forM dwarf stars, and previous dynamical masses in the literature.

Dynamical masses for two M1 + mid-M dwarf binaries monitored during the SPHERE-SHINE survey