Allow middleware and Route handlers to run together

I can't seem to understand why my custom route handler doesn't pickup the value set within a custom middleware. Here's what I'm working with:

// my route

router.post('/login', bodyParser.text({type: 'urlencoded'}), function(req, res, next) {
  if (!req.body) return res.sendStatus(400);
  console.log('access token is: ' + req.access_token); // This returns undefined

  var options = httpconn.httpOptions({
    resource: 'uaa',
    resourcePath: '/uaa/authenticate',
    method: 'POST',
    headers: {'Content-Type': ' application/x-www-form-urlencoded', 'Authorization': 'Bearer ' + req.access_token} // @todo get from the middleware that sets it
  });
  var httpRequest = application.httprequest(options, function(response) {
    response.on('data', function(chunk) {
        res.send(chunk);
    });
  });
  httpRequest.on('error', function(e) {
    res.status(500);
    res.send({'error': 'Authentication Failed: ' + e.message});
    return;
  });
  httpRequest.write(req.body);
  httpRequest.end();
});

// custom middleware

router.use(function(req, res, next) {

  redisSessionStore.getAsync('active_session').then(function(data) {
    req.access_token = data.access_token;
    console.log('retrieved access_token: ' + req.access_token);
  });
  next()
});

If I remove bodyParser.text({type: 'urlencoded'}) from the route, I get a Bad request error.

The custom middleware doesn't seem to run as seen in req.access_token returning undefined.

Any pointers please?