Unable to post data using OAuth

gistfile1.js

        YUI().use('gallery-oauth', 'io-xdr', 'json', function(Y) {
            var url = 'http://api.example.com/v1/update.json',
                data = { test: 'one' },
                cfg = {
                      method: 'POST',
                      data: { data: Y.JSON.stringify(data) },
                      xdr: { use: 'native' }
                  },
                signedURL,
                request;

            function onComplete(transactionid, response, arguments) {
                console.log(transactionid, response, response.responseText, arguments)
            }

            // Subscribe to "io.complete".
            Y.on('io:complete', onComplete, Y);

            Y.oAuth.ready(function() {
                signedURL = Y.oAuth.signURL("key", "secret", url);
                request = Y.io(signedURL, cfg);
            });
        });