I started off with a Honda nifty fifty as a field bike and then a Mobilette pedal and pop, slowly graduating up to a Yamaha XT500. That was back in 1979. That was when I got my first car and haven't ridden since. Modern bikes are scary.
BTW the mobilette was modified somewhat, being an engineering student at the time and all my mates were riding FS1E's and SS50's I was the poor relation especially at the traffic light drag strip.
So a few simple mods were:
1. Fit ace bars.
2. Fit a swivel joint onto the seat post so the saddle became a chest pad and you could then sit on the rear mudguard.
3. Lighten and blueprint bottom end.
4. Mount a model powerboat propellor and motor into carb. bell mouth and wire up to headlight. (Rudimentary supercharger).
5. Fill tank with 50% petrol, 40% tolulene and 10% castor oil, for that bit of lubrication.
At traffic lights, flip saddle vertical, slide onto rear mudguard turn headlight on wind throttle back and hang on.
Didn't last long but what a way to blow a motor!
Was everybody that daft when they were 18.