Fairly new to jQuery library, I'm trying to implement the following:

I've managed to bind the values of the control group to a variable, but I want to offer the user the possibility to enter a custom value in the spinner attached to the "Custom" checkbox.
Here are samples of the code I'm working on: (JavaScript)
$(function() { 
    /** Truncated code **/
    var intervalId, intervalDelay = 1000;
    var spinner = $( "#spinner" ).spinner();
    function handleSpeed(e) {
        intervalDelay = $(e.target).val();
    };
    $(".speed-bar").controlgroup();
    $("[name='speed']").on( "change", handleSpeed);
    $("[name='speed']").checkboxradio({
        icon: false
    })
} );
HTML:
<div class="speed-wrap">
    <div class="speed-bar">
        <label for="speed-rt">Real Time (2mn)</label>
        <input type="radio" name="speed" id="speed-rt" value=120000>
        <label for="speed-2x">x2 (1mn)</label>
        <input type="radio" name="speed" id="speed-2x" value=60000>
        <label for="speed-5x">x5 (24s)</label>
        <input type="radio" name="speed" id="speed-5x" value=24000>
        <label for="speed-60x">x60 (2s)</label>
        <input type="radio" name="speed" id="speed-60x" value=2000 checked>
        <label for="custom">Custom</label>
        <input type="radio" name="speed" id="custom">
        <input id="spinner" name="spinner">
    </div>
</div>
Side-quest: Is there an easy way to make the spinner height the same as the other buttons?
spinner.height(15);
