Your personal best top speed?

I would consider by personal "best" top speed one of my flat land sprints... going downhill fast is easy... sprinting really fast is significantly more difficult. I have hit 39mph

short downhill tarmac, on very old mountain bike.

far too slow.. will hope to recetify soon.
Not sure on a flat sprint--haven't done that (and tried very hard) for a while. I hit around 58mph on a downhill in the mountains north of Atlanta though. It was fun, but now that I think about it maybe not too smart. :D
my bike computer says my all-time high is 63. not sure i believe it. i've hit 40 several times downhill w/o pedaling.

gotta love my..cough...mass. ;)
I just finally put a speedometer on my bike so I now have an answer. I was going 39 last weekend through the Presidio in San Francisco. I wouldn't really consider it my "personal best" since it was just gravity pulling my fat butt down the hill. Although, it was fun and rewarding after just riding the climb that took me to the top of that hill.
shannons dad said:
64.3mph downhill with big rings and small cogs. Scary!!!:eek:

this sounds more like it. I ride a mtb but i have roadie friends that just take off when going long tarmac downhills....easily over 60mph...

here is me sitting upright, big fat knobbly soft tyres and cycling at max speed with a 42 chainring and 11 at the back (my biggest gear)...
47.6 on a mtb on road. Same spec as I trail race. Flatland top, 32 mph on a trail straightaway to the finish of a race.
34 mph straight flat - then I died - 1/2 of a tenth of a mile.:eek:

45 mph downhill .... and then the suburban had to pass me:mad:
I usually hold back at around 45 on downhills, because that's where my 52-12 tops out. Flat out, about 35 on pavement and 30 on dirt (which is a blast on a road bike).