47.5 mph on my Catrike Trail coming down off the Blue Ridge Parkway in North Carolina, feathering the inside brake on each curve as we headed down into town on the first day of the Cycle North Carolina ride a few years ago. We started in Blowing Rock and rode up the Parkway a ways, and then the ride down to the next town had a 12 mile downhill run full of curves. Of course, some old fellow on an expensive road bike went off the side and crashed on the way down. He had plenty of company, so I didn't stop, and two miles further down the hill I saw the ambulance headed up to get him. Sweet ride that one. By the way, the Catrike was very stable and fun at that speed.
Tractor Tom in Okeechobee, FL