The drive is still there, the money and time isn't. Kids in college, work, bills, other responsibilities.
You could a perfect candidate to join the Vintage and Post Vintage racing ranks. Similar to others, I didn't race when I was younger. I was 51 in 2013 the first time I ever rode a MX track, Podium 1 in Charlestown, Indiana. My first race at Action Sports in Athens was a few weeks later. Nerves, excitement, adrenaline, fear, anticipation, competitiveness, pride all exploded in a rush that I hadn't felt in years -hooked now and practicing to get faster to be able to race harder.
That is not even the best part. The best part has been meeting all the great people that race Vintage and Post Vintage. Many are regulars on this site. I look as forward to saying hello, picking up tips, and hearing stories at these races as much as the racing.
Plus seeing the bikes I used to look at in magazines as a teenager; they are just so damn cool.
My work/travel schedule is pretty intense but prioritizing 3-5 race dates helps keeps things balanced. My wife says I am nicer to be around after a race. And for getting hurt - sympathy attention and affection ain't so bad.
You could pick a bike from the era that you raced in the 80s and not spend a fortune.
DanO