@tgriffiths,
You can use the set method to update the chart title with the value from the input field as shown in the code-snippet below,
$('#load').on('click', function (evt) {
evt.preventDefault();
var title = $('#Title').val();
chart.title.set("text", title);
});
Kindly take a look at this updated sample project for an example on the same.
—
Adithya Menon
Team CanvasJS