Now it's time for the fun stuff. 

Yuri:  Last, how do you pace yourself? Did you preride so you knew what kind of times you should be laying down, or did you just go out and base your pace off your first lap?

Dave:  There are several possible answers to this one...as in what did I do in my most recent race, or what did I do in my first few races...but sticking with the theme of solo virginity (that sounds bad!), the short answer is start out a lot easier than you think you should, especially on a SS.  I've been training with power for several years now and have collected power data for long rides and a few 24 hour efforts as well.  From this data, one thing that is obvious is how much initial pacing affects late race performance.  Go too hard early in the ride and you'll slow sooner.  Fatigue in these events is inevitable but manageable with good fitness and a good plan.  Let's break the event down into 6 hour chunks.

Hours 0-6

This is a critical period of the race - not because you can win it here, but because you can lose it here.  Since this is when you are uber fresh and chomping to get racing (you've been tapering for a couple weeks and have been going stir crazy with extra energy) it will be easy to come out of the gate flying, and it will feel effortless.  Be conservative!  No matter how fast you go, you still gotta go in circles for 24 hours...go too hard here and the next 18 hours will be pure torture, or worse.  A prime example of going too hard early in the race happened last year at 24 hour natz.  All the big guns did their best to torch each other - and took themselves out of the race, one by one.  A hard pace means you aren't eating or hydrating well either, it all leads to CTD conditions.

I suggest setting some sort of limit for the first 6 hours.  This can be based off heart rate, PE, breathing rate, or power, depending on what you have available.  If using HR, the limit would be about 10 beats below LTHR, and you probably wouldn't want to average any more than LTHR-20 for any given hour.  You never want to go to the point where you hit your ventilatory threshold, where breathing just begins to get labored.  If you find yourself there, back off quickly.  At this point the primary fuel source is muscle glycogen which is good for about 2 hours.  If pacing by power, Coggan's level 2 is a good place to hang out, and limit any power spikes above L5.

So you're wondering what I'm talking about there...some of the fastest 24 hour riders come out swinging throwing down wicked fast first laps, sometimes faster than any team riders, and still go on to win.  It takes quite a few events under the belt to get a feel for what you can get away with.  Experience builds confidence.  Still, I've often pondered the pacing question.  Given what I've learned about power output (which determines speed & performance), it seems ridiculous to start a 24 so hard.  Yet, the winning riders often go hard.  Is it just because physiologically they are head and shoulders above the rest?  Or maybe it's best to make hay while the sun shines, so to speak?  The mental edge of leading the race?  Hard to say.  But for sure, in your first 24 solo effort, take it easy the first 6 hours.  If you find you have lots of energy left you will still have 18 hours to put it to good use.

In general, I don't pace by lap times at all.  It's all perceived exertion for me these days.  Ride the wheel of others when you can, but avoid getting on the wheel of someone riding like a XC event - super bursty - you'll want to ride as steady as possible to avoid those higher power bursts.  Ride relaxed, upper body loose, and get dialed into your nutrition plan ASAP.  You'll want to be taking in 300+ calories an hour, the sooner you get on track with this the better.

Hours 6-12

The first 6 hours don't tell you a lot about how you'll feel for the rest of the race, but in this period (6-12) you'll get strong indications.  In my first 2 events, there was a time around the 9 hour mark when I'd have trouble maintaining, probably because that's about the length of the longest training ride pre-event.  It was a difficult time.  Your circadian rythms are telling your body its time to get some shut eye.  Don't push pace at all in these hours.  This is the time to "settle in" and find your flow.  Your actual power output will likely come down considerably, and you are best served by a comfortable pace.  MP3 players were made for night riding in 24 solos...talking to others is a treat as well.  The cameraderie/vibe of 24s in general is so NOT norba, it's grassroots stuff where everyone is having a great time.  Soak it in, it becomes more apparent in the night. Keep your pits as short as possible.  Long stops in the night just have you starting the next one colder.  You don't have to ride hard, just ride...

Hours 12-18

The witching hours.  By anyones measure, the hardest part of the race.  Everyone slows towards dawn - just know this, accept it, don't fight it, flow with it, and keep the wheels turning.  Focus on keeping to your nutrition plan - and when I say "plan", I'm talking more about calorie goals.  Eating in the middle of the night is often difficult.  This is when you will make use of all the variety of foods you brought.  Be flexible in *what* you eat, just make sure you get the calories in.  I find that I need surprisingly little water in the night so can't get nearly enough calories by drink alone - but just be aware that solid foods take energy to digest.  This can be trouble, leaving energy reserves super low...if your support person can keep track of your calorie intake in calories/hour, they can help you avoid the total crash.  These are oatmeal hours.  You might find that sections of trail that were previously rideable become techy monsters.  Don't sweat it; when the sun comes up you'll see that line again.  This is also a good time to make little short term goals for yourself.  "Eat banana at turn x" or "make it through rock garden without unclipping" sort of stuff. 

If you have inner demons, they will surface in this period.

Hours 18-25

So you've been hammering away for 18 hours, only 7 to go!  After suffering through the dawn lap, the sunrise brings warmth back to the world.  It's amazing what this can do for you.  Hopefully at this point you're feeling OK, haven't cracked too hard, and have a little something left.  If you are in a good position, this is a tactical time.  Know where you are in the field in relation to others, and know that they are hurting as much as you.  If you haven't overcooked the pacing, you'll wake up nicely and have more to give...it becomes absolutely limited by fuel intake.  If you find that you are still racing, you'll want to go fast...but one fast lap in the last quarter of the race can leave you pretty drained.  So it's the constant tug - go hard, or eat?  If you can do both, great...if not, eat as much as you can in the pits.  I'm usually on to pepsi on alternating laps in this period...if you do a straight sugar approach like that, be sure to use electrolytes of some sort as an electrolyte bonk in the morning is a bad thing.  In a good race, I'm riding right at VT for most of the morning, and might even have to dig deep for a lap or two.  Despite the hard breathing, power output isn't much, it's just that by now the primary fuel source is fats & it takes a lot more oxygen to burn them.

On tactics:  you'll need help from your support crew here.  The idea is to do the least amount of time on the bike to achieve the highest possible placing.  You're racing, right?  You could find yourself at the front, but close - which might mean you have to crank really hard to come through before noon so you get the honor of another lap.  Or, you might be in a bit of no mans land, where you can stop at 11am and not lose a spot.  If the SS field is small (not likely in CA I'm thinking), the gaps could be large.  Just don't convince yourself you will stop at 11am if there's any chance whatsoever you need to keep it rolling.

More on tactics:  if you have the good fortune to still be racing (95% or riders are in survival mode right now) it is a huge mental game right now.  Actually, racing always is...but especially so after everyone has been to the bonk and back already.  You may be really tight with one or two competitors.  If you lay down a lap that is substantially faster than a previous lap, it will strike fear and doubt into your competition.  Or, really motivate them...depends how tough they are.  Just know that these are the type of games that go on at the pointy end of the field, and if you are still racing, everything you do will have consequences one way or another...OK so this is a more advanced topic, but Yuri is a fast, salty dog that just might find himself in this position.

Finally, you'll come into the timing tent for the last time, and with that arrival a sense of accomplishment you've done something out of the ordinary, something big.  Your body will know it too.