If you did 50 miles at the last Century, you _can_ do 100km right now! I promise!! That's only 12 more miles!
I love to do this thing, at the end of my longest ride ever, whatever the distance. Try to imagine what it would be like to go another hour, or two hours, or whatever. Most of the time, it seems like if I _had to_, I could do it. Probalby wouldn't be pretty, but, I _could_. Add on a couple weeks recovery, and your body is _ready_ for a longer distance!!
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson