Good luck! I did my first STP somewhere around 1995 (?). At the time, I was young, had lots of seat time, but didn't know what I was doing for a long ride in terms of food, avoiding dehydration, etc. I also did it on a mountain bike with slicks mounted. That year I survived 114 miles to Winlock on day 1, then the balance to Portland on day 2.

Honestly, the worst part of the whole thing was getting back on the bike on day 2.

The next time I did it, I shot for the 1-day in 2003. I was in very good shape from rowing but had no recent cycling experience. Got into town, borrowed an all aluminum road bike (a double), did a 40 mile training ride and a 20 mile training ride the week before, then just went for it.

It wasn't pretty -- left at 4:45am and didn't get in to portland 'till 8:30pm -- but I made it. Also, I was numb for about a month afterwards.

Let me just say that now that I'm getting back into cycling, I make sure I have the proper gear. It makes hours of seat time so much more survivable, wicks sweat, etc. Just did 144 miles and 10k feet on Sunday. It still takes a couple of days to recover, but it's better than being numb for a month.