Aha, well spotted. Yes, both 1983 models, the 500 is a standard "maggot", the 650 is a US spec custom, never sold in the UK. Lusted after an obruT for years, never had one, never rode one. Some good ones still about but parts for them are almost impossible to obtain. I'm a long time member of the CX-GL MCC, we have about 300 or so UK members plus another 100 or so worldwide.
Alan.