Tim is that the old Silver Austro model ?
If it is, I reccommend removing the plastic box that covers the chain.
It will increase wear and need for lubrication slightly, but if the master
link should ever pop, the chain winds round the rear sprocket and will
vault you over the handlebars at a very inopportune moment.
The Austro, while not very fast or powerful, is an very nice simple and
reliable design that will last a good many years, and is fairly simple
to get parts for, as well as being fairly tough.
The only mods I ever did to mine were a slightly larger carb and a
different sprocket for a little more takeoff, you lose about 2mph in
top speed, but it beats being "bumped and dumped" by some jerk
in a car when the light turns green.
Also, the Austro will run well in below-freezing temps, don't know
if the moby will or not, all in all, it makes a damn good backup 'ped.