How to change the colour for round blue circle pin

Question

I am using bing map on asp.net application, the default pin icon 'pin55light' which is in blue color is shown on the map. I am wondering if there is any way to change it to orange and make a size bit bigger?
Here is the code, for pin2 i am using custom icon but pin1 is having default icon. Is there any quick way to change the back color of default blue circle icon?
function themesModuleLoaded() {
map = new Microsoft.Maps.Map(document.getElementById('myMap'), {
credentials: BingMapKey,
zoom: 7,
center: new Microsoft.Maps.Location(546, 787),
theme: new Microsoft.Maps.Themes.BingTheme()
dataLayer = new Microsoft.Maps.EntityCollection();
map.entities.push(dataLayer);
var infoboxLayer = new Microsoft.Maps.EntityCollection();
map.entities.push(infoboxLayer);
infobox = new Microsoft.Maps.Infobox(new Microsoft.Maps.Location(0, 0), {
visible: false,
offset: new Microsoft.Maps.Point(0, 20)
infoboxLayer.push(infobox);
AddData();
function AddData() {
var offset = new Microsoft.Maps.Point(-3, 2);
var pin1 = new Microsoft.Maps.Pushpin(new Microsoft.Maps.Location(44, 66));
pin1.Title = 'Vendor';
pin1.Description = 'description';
Microsoft.Maps.Events.addHandler(pin1, 'click', displayInfobox);
dataLayer.push(pin1);
var pin2 = new Microsoft.Maps.Pushpin(new Microsoft.Maps.Location(11, 55), {
icon: '~/images/icons/pushpins/pins/pur.png',
width: 30,
height: 40,
text: '1',
textOffset: offset
pin2.Title = 'title';
pin2.Description = 'description';
Microsoft.Maps.Events.addHandler(pin2, 'click', displayInfobox);
dataLayer.push(pin2);
}function displayInfobox(e) {
          if (e.targetType == 'pushpin') {
              infobox.setLocation(e.target.getLocation());
              infobox.setOptions({
                  visible: true,
                  title: e.target.Title,
                  description: e.target.Description,
                  width: 170,
                  height: 100,

Answer 1

The whole idea of the theme module is that it changes all the look and feel of the map. You can't override those. You are better off using a custom pushpin without the theme module.
http://www.bingmapsportal.com/ISDK/AjaxV7#Pushpins2
https://rbrundritt.wordpress.com/2014/10/02/correcting-anchoring-pushpins-to-the-map/
http://rbrundritt.wordpress.com