Edit in JSFiddle

function initialize()
{
    var map = new google.maps.Map(document.getElementById("map"),
    {
        zoom: 14,
        center: new google.maps.LatLng(18.5010, 73.8485),
        mapTypeId: google.maps.MapTypeId.ROADMAP
    });
    var bikeLayer = new google.maps.BicyclingLayer();
    bikeLayer.setMap(map);
}

<html>
<head>
<title>Google Maps API v3 Example: Bicycling Layer</title>
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>
<script type="text/javascript">
</script>
</head>
<body onload="initialize()">
<div id="map" style="width: 530px; height: 230px"></div>
</body>
</html>