Is it the 600 or the 660 ?My MZ has the XTZ600 engine.
I wanted an XL600 in my youth.
I always liked the rotax derived engine they first put in the early scorpion (i think)
I had an ex army Armstrong MT500 with that engine and loved it apart from the (bastard) left foot kickstart and lack of electric start, would do 90 flat out and pull you up the side of a house at more sensible speeds went all over on that with off road biker types an didn't get stuck once ..... A mate spat the belt on it at about 50mph, we just put a new belt on and away she went (safe engine so the squaddies couldn't kill them)
I have always wanted the 350 electric start version that are badged as harley davidson but they are 2,500 to 3000 now and I don't have anywhere near that amount of brass, shame really as it would suit my meagre needs