on your Piaggio is there a pull out holding the rocker arms in place , it makes it so easy to change shims on the valves, just pull the plug thing and slide the rocker arm over , and install the right shim, slide the rocker arm back and replace the plug thingy, your done,. I changed the valves at 20,000 Km.s only one exhaust shim needed to be changednext summer I will check the valves again at 40,000 Km.s it just passed 32,000 Km.s in sept.
