Hi I have a ccm 604 RS, too. It`s also from 2003. I bought it from a real a..hole, he obviously lost the oil dipstick and further more he gave it to me without any oil in it!!! So now here I am with a broken motor with only 4000 miles... If anyone knows where to get a good used one or perhaps a new one (I prefer used) please let me know. If anybody is looking for a good ccm 604 rs let me know, too. ;) I am running it with a 500 ccm rotax motor but as soon as I get hold of a 600 ccm motor I will built it up again. I am from Germany so please ignore any misspelling. :)