Originally Posted by Menel

I've hit 51 before. Buddy I was riding with coming down Cheaha mountain last weekend said he hit 52. It's not scary if your bike is well maintained and properly setup. My limited experience has been that bikes are perfectly stable at high speeds, even with the occasional bump. I've clipped a reflector on the road on more than one occasion at 40+, it's not pleasant, and it's ideal to avoid it, but your not going to be instantly thrown off the bike.

Just keep your eyes open and watch the road.

Confidence comes with experience, maybe this will help?
http://www.youtube.com/watch?v=iBtWB8TM9wg

I've gone down (edit: as in hit the ground) at 35ish. It was not pleasant, road rash from shoulder to shin, I still have some residual scaring on right knee and knuckles. But I was healed enough to be back out and running/cycling by the following weekend. Just got to HTFU, and tegaderm is awesome stuff.