I started riding after 30. I'm 44 now and I started riding when I was 41. I took a Honda Dirtbike course since I knew nothing about motos at all. My girlfriend and daughter came along too- her daughter had never even driven a car before and had zero clutch experience. The course was great- we all had a blast and learned a lot. I knew bikes would be in the garage in short order.
Fast forward to present day: Girlfriend has a new dirtbike on the way (Honda CR250, she started on a XT225) to match her '13 Ninja 300, daughter is still on her TW200 and I've got three bikes now: DRZ400s, Triumph Bonneville 2006 cafe racer (my "cool" bike- bought off a guy in Las Vegas who spent way too much money making it look very sweet) and '13 DL650 V-strom (my go far bike). We all took the MSF course and we all have our M1 licenses.
We ride carefully and I always think about the statistic that says I'm more likely to wreck in the first few years of riding so I ride very conservatively. I've done a bunch of moto trips both dirt (southern Baja) and road (best was a 4 day, 1500 mile trip from SD to Central Cal and through all kinds of twisty backroads up there with my brother who rides too)- I'm messed up on the traveling part of it. I conquered my fear of riding through L.A. on the 405 and have made that freeway my bitch. I respect her, but I'm not afraid to ramble through the LA monster when I have to.
I'm not bummed that I didn't start earlier- things happen when they are supposed to, but I do take the advice, "Ride while you can" to heart; when I get a chance to get out on the open road- I do.