
Welcome on board Tony
Plenty of mods you can do to reduce the surging, alot of which are either free-to-do, or cheap and easy. Here's some reading homework for you...
Join XT660.com supporters to access the “Ask Kev” 1:1 technical help section -
http://www.xt660.com/payments.php

Twist-grip mod -
http://www.xt660.com/showthread.php?p=154983
No Cost Mod

Cush drive rubber mod -
http://www.xt660.com/showthread.php?t=12422
No Cost Mod

Adjust your CO -
http://www.xt660.com/showthread.php?t=55
No Cost Mod

Adjust your TPS -
http://www.xt660.com/showthread.php?t=56
No Cost Mod
Kev fuelling mod -
http://www.xt660.com/showthread.php?t=194
O2 controller -
http://www.xt660.com/showthread.php?t=14746 (current version from post #165)
Click on the link in my signature for the full list of all the mods available – and it’s a long one!