This is not about Mopeds ...sorry....(old motorcycle info)
One fun thing here Ron is that we both have extensive experience on the same old bike.... My all time biggest mileage is on a '71'CB500 (with a '74' 550 motor)... I put about 55,000 miles on that thing...still have it... One day I pulled up to a gas pump and when it dropped momentarily to a sub-idle speed... it stopped... instantanaeously, mechanically...not just stalled... I thought ...well that was different... I figured it either dropped a valve or broke the cam chain or something... the engine wouldn't turn at all...so I pushed it 2 miles home..... I parked it and have never taken it apart (10 years or so)
I bought it as a basket case with a whole bunch of new parts... the guy had taken it apart and was going to make a "cafe racer" out of it.. then never did it... I bought it for $800 in prob 1981 and rode it for 10 years... It had brand new Lester Mags, JR exhaust, Martek ign advancer, Magura clip-ons, small cafe fairing, S&W air shocks, chromed swing-arm (all new!)... and then I lucked out and a friend at a used parts place found a brand new Yoshimura camshaft in its original box...new.... I rode the heck out of that bike, for a long time...and it was pretty fast too..ran dead even with an '85' Kaw GPZ550..up to 105mph...then the GPZ got into a wobble.
It was very warn out when it died... blew a lot of smoke...clutch slipping a lot...chain and sprockets gone... cables gone...fork tubes had been extended and rechromed and the chrome was gone where the most wear spot is.(extension above the triple clamps for the clip-ons)
Anyway..... that was kind of fun, telling you all that stuff... maybe it will run again someday.
I imagine you've seen the Yam XS650 Society site?
I mostly ride a "80" Suz GS1100E... but have other stuff too.
For peds I currently have a Honda 79 PA50, and a Suzuki 82 FA50.