diff --git a/lib/ClientBase.js b/lib/ClientBase.js
index 35b0da6..dff0e8b 100644
--- a/lib/ClientBase.js
+++ b/lib/ClientBase.js
@@ -15,6 +15,12 @@ var request       = require("request"),
 var BASE_URI           = "https://api.coinbase.com/v1/";
 var TOKEN_ENDPOINT_URI = 'https://www.coinbase.com/oauth/token';
 
+var generateExpireTime = function () {
+
+  var timestamp = String(Math.floor(new Date().getTime()/1000) + 15);
+
+  return timestamp;
+};
 
 //
 // constructor
@@ -53,29 +59,21 @@ ClientBase.prototype = Object.create(Base.prototype);
 // private methods
 //
 
-ClientBase.prototype._generateExpire = function () {
-
-  var timestamp = String(Math.floor(new Date().getTime()/1000) + 15);
-
-  return timestamp;
-};
-
 ClientBase.prototype._setAccessTokenOrExpire = function (url) {
 
+  // OAuth access token
   if (this.accessToken) {
-    // OAuth access token
     if (url.indexOf("?") > -1) {
       return url + '&access_token=' + this.accessToken;
     }
     return url + '?access_token=' + this.accessToken;
-  } else {
-    // Expire for API key
-    if (url.indexOf("?") > -1) {
-      return url + '&expire=' + this._generateExpire();
-    }
-    return url + '?expire=' + this._generateExpire();
   }
-  return url;
+
+  // Expire for API key
+  if (url.indexOf("?") > -1) {
+    return url + '&expire=' + generateExpireTime();
+  }
+  return url + '?expire=' + generateExpireTime();
 };
 
 ClientBase.prototype._generateSignature = function (url, bodyStr) {
@@ -146,7 +144,7 @@ ClientBase.prototype._postHttp = function (path, body, callback, headers) {
   if (path.indexOf('http') === 0) {
     url = path;
     body = body || {};
-    body = _.merge(body, {"expire": this._generateExpire()})
+    body = _.merge(body, {"expire": generateExpireTime()})
   } else {
     url = this._setAccessTokenOrExpire(this.baseApiUri + path);
   }