The learning stage before ....

Must be the learning stage you go thru just before you get a Z13 with a sidecar :lol:

Well at least he has graduated to a real bike

Actually, back in 1983 at the first Griffith Park USCA rally I attended, three of us sat and talked about how to be safe while learning and not tip a rig over to the left in a right hand turn taken too fast. Well, at least for us with sidecars mounted on the RIGHT side! I fabbed up a triangulated brace fr the left side that had a castered 8" tire on it. That tire only cleared the road by 2", and stuck out about 18", so it kept the whole rig from even starting to roll over, but still let the rider know he went too far in speed in a right hander.
So, don't laugh at those training wheels! A heavier-duty version of them is very useful for getting a feel for driving a sidecar rig. KZA13 I'm sure you know well what I'm talking about! They aren't easy to just jump on and drive. It's like learning to ride a bicycle all over again. I've had two of my own rigs crashed by friends who were long time bike riders, but had never driven a sidecar rig and wanted to try it. "Here, hold my beer and watch me do this!". Never again!