how did your restoration go? I bought a running, clean, 83 tempter 3 months ago. ran wonderfully, but unknown to me the cam chain was worn and loose. it broke last month, and is now in pieces being repaired. I am finding certain, model specific, parts are not readily available. I am looking into a 1989 gs500 cam chain guide as a hopeful fit to my 650. I have heard the engines are the same. Gs 500s are so cheap and plentiful, that I am even considering it could be a replacement engine, if ever needed. any ideas? I hate the idea of a smaller engine, and one that hurts the integrity of the model, but if it simply can not be fixed at any point... I bougth it to ride, not for show. oh, and for U.S.: about 40-45 mpg