The information included with the Flying Wheels Summer Century (FWSC) packet I received indicated that if I was able to do the 100 miles at the FWSC, then I would be able to do the STP in one day because of the hills at the FWSC. Does anybody have any insight as to whether that is true?

Insight, not personally (today was my first century). I did the Flying Wheels century as well. I feel what they mean is if your muscles are fit enough to do the Flying Wheels, then they should be okay to do the StP. Reason being that even though it's 200 miles vs. 100 miles, the 100 miles you did today have about double the elevation gain of the 200 miles of the StP. FW is 40 ft elevation gain per mile and StP is 10 ft elevation gain per mile. The elevation gain will eat up your glycogen (limited amount) but flats you should be running on fat (of which you will have more than enough to last you a day). I think a bigger issue of doing the StP is being on the bike for 10-14 hours during one day.

Well, it's true to an extent.

They're really very different rides. Flying wheels has the hills, but you can take a *long* time to do it if you want.

STP, on the other hand, gives you from 5AM to 9PM, which is 16 hours to go the full distance (and to finish before the finish line closes). Figure that you are going to spend a couple of hours at the stops along the way, and that gives you 14 hours for 204 miles, or 14.5 MPH.

STP one day has a bunch of paceline time, so if you can find a good group, you can make significant time on the flats - and there are a lot of them. You may have issues on the rolling hills in the second century if you aren't using to riding groups on that sort of terrain.

The other big difference is nutrition and hydration. Things that you can get away with in a century will come back and bite you in a double.

I've only done both one year - in 2006. I pulled up my times:

FW: 101.2 miles, 5:56 elapsed time. This had a fair amount of paceline time on the trip up and back to monroe.

STP: 203.4 miles, 11:46 elapsed time. The first century was 5:26 @ 18.4 MPH with some nice pacelines. At about 120 miles I ran out of salt (you really need to be careful about that on long rides), and rode the last 80 miles by myself out in the wind (I felt crappy enough that I couldn't ride in a paceline). I got in at about 7:30 that night - it would have been sooner but I had to stop and rest more than I'd like because I was sick.

If you can finish flying wheels in a reasonable time and still feel like you might be able to ride another 50 miles, then I wouldn't worry about STP one day. On the other hand, if you feel like you never want to see your bike again before you start up fall city/issaquah, I'd be a bit more concerned.

Hope that helps.

I agree with the previous poster that they are totally different rides. I found that the first 100 in STP were pretty easy and I felt like I could do more at the half way point. For Flying wheels I was "done" after the 100. I averaged 16.5 for the one day stp, the last 30 miles suck sine it feels that after you cross into Oregon you should be there but you have 30 miles to go from that point.

It is up to you about whether you feel that you can handle the saddle time. Trust me, you will be sore and every part will hurt about 180 miles into it.

I've done no less than 4500' of climbing on any of my long (century+) rides so I know that the hills aren't going to be an issue with STP. I was starting to get worried, because until yesterday I hadn't done any rides longer than 108 miles, and on that 108 miler I bonked around 106 miles.
I made the determination it was a combination of the my going out too fast, pushing too hard for too long, and the ridiculous heat (it was that 92 degree day for Tour de Cure). I used the 7 Hills of Kirkland century to learn how to better pace myself, and yesterday's FWSC plus 25 extra miles to really prepare myself mentally for STP in one day.
My course took me from the top of Redmond Ridge, through Trilogy golf course and down 133rd to Avondale to get to the start line at Marymoor. Then I rode the century, exited the north end of the park and did some mileage around Bella Bottega area before heading back out Avondale to 133rd. Mile 117 was the bottom of the hill on 133rd (a 3 mile climb to the crest of Redmond Ridge) and I didn't feel like I was dying on any point during the climb.
I managed a 6:30:00 century yesterday, and that was hilly with no pacelining. I'm hoping for similar back-to-back times for STP, if not faster. They only give you 16 hours (2 hours short of the UMCA regulation double century finish) and I'd like to roll in before the finish line closes.

Having ridden the STP several times in one day and I did the FWSC yesterday, there is a difference between the two rides. For me, the major difference is nutrition and hydration. This means eating when you are not necessarily hungry and drinking when you probably aren't thirsty for the STP. I have found that how I eat and drink in the first century has either set me up for a painful second century or allowed me to enjoy the second century. The exertion level between the two might be similar due to the amount of climbing in the FWSC but not the amount of pedaling done for the STP. This is why I say nutrition and hydration play a critical part as you will need the energy in the closing 50 miles of the STP. It is bad enough mentally to think you have been on a bike for 10+ hours but to add the fighting with severe leg fatigue makes it doubly so.

Last year they held the finish line open beyond 9pm. I heard some people came in around midnight, I was surprised.

Thanks everybody. I honestly finished the FWSC thinking there was no way I could do the STP. I averaged 16.5 miles (thank you pace lines) for the FWSC and felt that I could have kept riding at a decent clip (if the terrain was flat-ish). The hills, however, knocked my dork in the dirt! Hopefully I can catch some good (19-22mph for me) pace lines to help me along.

Thanks again everybody and good luck to those who are riding the STP this July!

I've done two one-day STP's (a lot longer ago than I want to admit) and I had never ridden even one century before either of them. In fact, for my first STP the longest single ride I have ever done was 50 miles. The second time, I trained harder and rode an 80-miler once. Admittedly, this was back when the start line was at the Kingdome and the ride was a little shorter, but I finished in 14 1/2 hours the first time and 13 1/2 hours the second time. There were some amazing pacelines during the first half and I got to Centralia in well under 5 hours. The second half was just awful with rolling hills and headwinds- I bonked really bad for a while and wasn't sure that I was going to make it at one point. I even got a flat tire on the Longview bridge and had to repair it right there on the bridge deck. It just goes to show that if you're naive (or stupid) enough, you can do it with little training if you can find other people to pull you most of the way.