She'll be fine, just don't take any corners too quickly if it's loose underfoot (underwheel?) - mind you, your bottom will probably dictate a comfortable speed over the bumps - and, as SatNav says, give the bike a bit of a wipe down afterwards - and more importantly make sure the chain's clean and lubricated, especially if it's dusty. A coating of sand is rather good for prematurely grinding down chains and cogs.