I've raced seriously for 7 years.
I raced against Justin Buckelew when I was 3 and 4. Then stopped and picked it back up when I was 17.
It got old because I've had to many concussions lol... never broke a bone but always landed on my head, whether it was jumping a 120ft table top, or hitting a tree at 35mph, it was always my head.
It also got old because I could never put in the dedication that I could as when I was younger. I work full time and have school now, so finding the time to work out and stay in shape to do a 3 hour race through the woods was getting harder and harder to come by.
Just last month I had 5 bad rides in a row and just hung it up. Still have my KTM 250 XC, I'll probably go back.....just not as competitively.
I know what you mean about ripping though, I love the feeling.