As Minder has quoted, use an automotive relay .I working on a 48vdc motor but every time I turn it off with a relay ,the relay gets destroys.
Being 24v coil, most truck relays should suffice.
I imagine the motor is on load when switching on and off........if so, they can draw quite an amount of startup current, at least 4 times full load.
Given that, I would tend to use a starter solenoid, however there may be some restrictions on duty cycle.
Alternative would be a 100A contactor.
That should stop it's monkeying around, although could cost a few hundred bucks.
One additional query though, why use such a motor in the first instance?
Perhaps if you describe what you need to achieve, there may be better alternative drives.