Monday, March 26, 2012

San Ysidero Dirty 104

The San Ysidro Dirty Century was my first race this year, and a unique event. The SYDC is mostly a gravel race with a “short” section of singletrack. Historically the course has started and finished from a brewery in Rio Rancho, New Mexico. Due to land access issues there were some last minute course changes. Much respect to Lenny Goodell – the event organizer – for pulling together a great backup plan. In reality, this was probably a better route. (Here’s the route on Garmin) Previously the full version of the course was 123 miles, but the revision reduced that to 98. However, this placed the singletrack at the very end of the course – a devious sting in the tail. Hoping to bring the Mosaic I asked Lenny if this singletrack was CX bike friendly. Here’s his response:
Hey Shane, this is from Chris Hereford who always does SYDC on SS CX. Also he is a very good technical ride, so he may have a different view of White Mesa on CX than others…
“CX bike is the only way for SYDC. The singletrack isn’t severe enough for an MTB. Just my opinion, after five years on a cx bike on the course. And this has all been on a SSCX bike with 42×18. Suspension isn’t necessary for the long day, but many enjoy the comfort of an mtb. Yes, it is mostly dirt road, with occasional sand pits, and that’s when I’ll have to walk sometimes.”
That sounded positive to me. The videos and photos I had seen of the White Mesa trails seemed to confirm that it was mostly flowy mellow trail with just a few rocks tossed in.

Ok, so how did it go?
The day dawned bright, crystal clear and 50 degrees at 7am. After some rushed preparation – my phone/alarm decided to crap out – I was ready to go. The check in and line-up was pretty informal. Lenny called the start and we were off. The lead pack blasted ahead pretty quickly. I managed to keep up for the first 7 miles or so, even leading for a brief ½ mile. This group was going really fast (around 18mph) and I knew I wouldn’t be able to keep this pace all day. I fell slightly back just before we turned right on Pipeline Road. This was also the point where we faced a bit of a headwind and I was really wishing to be in the paceline to draft. Alas, this was not to be and facing the headwind alone I fell farther and farther behind. The group was still in sight however until I made a wrong turn.

Lenny starting us off.

Horse play on Pipeline Road. 

A very generous soul was kind enough to drop water and whatever else we wanted about the 18 mile mark in the course – a point where we turn right, make a big loop and reconnect at about 65 miles in.  The drop ended up being closer to the 15 mile mark at a different intersection where we were to turn left. Something felt off but a local I was riding with assured me we were to go straight. Then the Garmin told me I was off route. There were not a lot of tire marks but I did see one rider ahead and three others joining us behind. I asked one who also assured me we were on route. Things didn’t seem right by the mileage when I checked the cue sheet. After asking about the Ridge Road intersection I confirmed that we were indeed off route about 3 miles. I told this to the others around me. They elected to continue on, which would have reduced the distance by ~5 miles, while I turned back to get on the official route and add 6.

Back on the official route and trusting the course in the Garmin all pressure was now off. I was previously struggling in my attempt to keep up with the lead group, but with the added 6 miles and whatever distance they covered I was likely at least 12 miles behind and completely unable to catch up.

Ridge Road
Had I stayed with the shorter course I would have missed ridge road, which was a fantastic a scenic stretch I’m glad I didn’t miss. I took it super easy and rode a couple of very mellow miles chatting with another rider, Charlie, before opening it up and going at my own pace. This big loop of the course wraps around Cabazon Peak. 


After a brief 4 mile paved section I was on the North side of the peak and passed a large group who I later learned had also gotten off route. One rider from this group, Billy, caught up to me and we ended up riding and chatting for most of the rest of the route. I made the decision after my “bonus” miles that I would take the time to be a be a bit more social rather than simply try to keep my own pace the entire ride. I probably could have finished faster had I gone at my own pace the entire time, but I would not have had the same experience. The people I met on the SYDC made the experience special for me at least as much as the fantastic weather and the amazing views.

Billy on the drop bar Niner. I was coveting that fork on the singletrack. 
Billy was on a single speed, drop bar, 29er with skinny tires. I’d often move ahead on many descents and Billy would catch up later. While I can often keep up on the flats, Billy and many other experienced riders always jet past me on the hills. With only 18 months of riding under my belt and only 4 months of actual training it’s becoming rather obvious where I need to focus my training efforts in the future.  For now and the rest of this season I need to focus on my endurance, but hill climbing will be the training menu for next year.

Billy and I finished rounding Cabezon and returned to the drop. After a quick refill, we headed down the last 15 miles before the singletrack. I went off on my own from here at my own pace. I had played tag with a woman on a full sus 29er for the last hour or so. I called tag when I caught here again and sped past down the road. Near our last turn at the natural gas compressor station I met Todd and his squeaky wheel. Todd had kept up with the lead group till a broken spoke and a wounded wheel led his tubeless setup to fail. As luck would have it his spare tube had a broken valve and Todd was forced to hike till another CX bike caught up with a spare tube. He and I rode into the White Mesa Trailhead where he split off to finish and I elected for more punishment. Todd had kindly offered a place to stay in Santa Fe for the night, but losing his number and my dead phone nixed this option.

I rolled into White Mesa at just under 6 hours and around 90 miles. Expecting the last 15 miles to be fun and mellow I figured one water bottle to be enough (big mistake). I wasn’t on the trail for more than 2 miles before I had slowed to a crawl. I was pretty obvious even in this early part of the trail, that while you could ride these trails on a CX bike, it was far from a wise decision. (From what I can tell I was the only fool to ride it on a rigid CX bike this year.) After this first two miles I heard a fast rider come from behind and yell “Tag!” I knew I wouldn’t see her again. Billy caught up shortly after that and we both endured the remaining miles together. Billy had ridden this trail system at least twice before and his wayfinding experience was extremely helpful. White Mesa has a fantastic map at the trailhead and promises numbered intersections with maps at the junctions. Well, some of the junctions were numbered and had those maps, but others were vague. We finished off the route and rolled into the finish together – not DFL. Ironically the first 90 miles took 6 hours while the last 15 took 3.

A true ridge route

Just some of the exposure.

Yup, we came down that amazing trail on the ridge.

The trails at White Mesa are amazing. They really differentiate this route from all other grinders that I know of. The views and exposure are fantastic and scenic, but there are quite a few steep ascents and descents, a lot of rocks, a bit of sand, and the sections which could have been smooth had dried to cement like hardness with many dips and potholes. This was beating me up for the entire 15 miles. It was easy to enjoy the views, but honestly it was hard to enjoy the actual ride on this bike. I’m glad I did it, but wish I had the right bike. (FWIW a hard tail 29er would be perfect for the full ride – I just don’t have one. I have a double squish, but thought that would be overkill on the road. Any time I lost there I would have easily made up on the singletrack.) There’s a reason the vast majority of folks were on mountain bikes. I realized that Chris Hereford (the guy quoted above) really is a complete bad ass.

Climb-a-bike. It's not just a steep gully. The rock Billy is standing on requires some scrambling just to get up on. 

Billy is about 200' below me on that sandy, steep trail.

At the finish I connected with a couple of other Colorado riders Aaron and Phil. I had filled a growler at Oakshire with their Overcast Espresso Stout (my personal favorite) before I left Oregon. I had been looking for an occasion to open this thing and I was certain this was near the end of the shelf  life. I can't really drink more than 2 oz of beer after a long ride, so sharing this at the end of SYDC seems like a good choice. Sadly, some combination of the extra time in the bottle or the extra heat in the back of the car meant that the beer had turned. A quick sip confirmed that. I went to dinner with Aaron and Phile where we replenished some lost salts with the salty rim of a margarita. After breakfast at the Bad Ass Coffee Co we both headed for home, but coincidentally reconnected in Trinidad, CO where I had stopped for lunch.

The cage for this bird is about 15' tall. 
There are many great old buildings in Trinidad, but many appear abandoned. 

Lessons learned: 
  • If you don't put sun screen high enough on your forehead you get little triangle tan lines. 
  • Sun sleeves work fantastic, but slide down in the back sometimes leaving an exposed strip (yup got a burn there too.) 
  • Some really cool people do these rides. 
  • The route loaded in the Garmin is sometimes more accurate that advice from locals.
  • Don't bring a butter knife to a sword fight. 
  • Dark beer lasts a while in a growler, but not six months. 

The AntiEpic is in two weeks. I know the roads there so I’m safe on the Mosaic. I’m hoping to pull off a White Rim trip in another two weeks after that and call it a training ride, but on the 29er.

Saturday, March 17, 2012

Swiss recon

With a 3:30-4:30 ride planned I was able to connect with Adam, who was game to do a bit of an adventure ride. The plan was to do all of the Switzerland Trail from Boulder. The Switzerland trail is West and pretty far uphill, so it was a little uncertain whether there would be snow or mud.

The climb up four mile road to the start of the Switzerland was pleasant enough and the first several miles were outstanding. The Switzerland Trail is a pretty rough road that's not maintained. We actually began in the middle and headed North. The first portion was great with very little snow, but after crossing Gold Hill Road we quickly hit a long stretch of deep snow. This section is North facing so it needs a bit more time to dry out.

Adam and I decided to head back down through Gold Hill. We stopped in at the cafe in Gold Hill where Adam indulged in the spinach quiche. The route off the hill was steep, fast and winding, and very scenic but only partly on gravel. I'm not sure a huge hill and a huge descent was the best training for the constant up and down routes I'm doing, but it was a hell of a ride. I'll be back. Enough word, time for some pix.

Wednesday, March 14, 2012

Testing: Secret Drink Mix and Allen's Rice Bars

The pre-ride of the AntiEpic route I did with Ben was a nutrition test as well. I had just discovered Skratch LabsSecret Drink Mix(SDM), and this was the first long ride I used it on. SDM has fewer calories and more electrolytes than many other drinks. It also uses only natural ingredients – the flavor (orange, raspberry, or lemons & limes) comes from crushed freeze dried fruit that each flavor is named for. You can really tell in the taste. I’ve never had anything that tastes more like a fresh raspberry than SDM. Besides great flavor and good ingredients the stuff just works.

On the Kiowa 808 I only managed 3 bottles in 80 miles. This time I finished 6 full bottles in 102. SDM is simply easier to drink. I didn’t have to force myself to drink because I had a hydration schedule, and wasn’t drinking simply because of the weather conditions. I really feel like the light flavor and lack of calories just worked for me. It’s hard to want to stop and relieve myself (albeit easier in lonesome gravel country) but I know that if I have to go every so often I’m probably appropriately hydrated and likely to both perform and recover faster.

SDM doesn't contain anti-caking ingredients so make sure you protect it from humidity. They sell a metal canister, but I have some glass canning jars that work well for me. Besides the 1 pound bag you can also get singles. Be warned though, the singles only make 500ml and most water bottles are closer to 750ml. If you choose to get the big bag it's easy enough to find tiny zip lock bags (spice section at Whole Foods) that you can load up with enough for a single bottle. The large bags use a scoop to measure the serving, but the scoop isn't in the bag, so if you get it at a store make sure you ask for the scoop on your first purchase (if you purchase direct they'll send ya one). I'm not sure why it's not in the bag, but really you only need one and getting a new scoop with every bag would just be a waste.

Tiny flecks of raspberry skins in the raspberry flavor. Mmmmmmm....

Rice, rice, baby..dum dum dum da da dum dum...
The other thing I tried was Allen’s Rice Bars. Allen Lim is the main man behind SDM and he coauthored a book with chef Bijou Thomas The Feed Zone which describes real food recipes for athletes – some of which can be used on the bike. Allen’s rice bars are one of the top recommended recipes and made of rice, bacon, eggs, Bragg’s aminos and brown sugar. The idea of real food was highly attractive, but I admit that I was pretty skeptical of having bacon and eggs with rice on a ride. It just didn’t sound like something my tummy would want. Well, I made the bars last week and tried them. Damn, those are good! I had a harder time saving some for the Sunday ride. But would they work on a long ride?

In short, yes. They were tasty enough that I looked forward to eating them, and when I did they did not feel like a rock in my gut. Other times when I had tried something more solid (Clif, Luna and Mojo bars), or even liquids with protein (i.e. Perpertum),  I always felt like my stomach had some work to do to digest things. I felt slow for a while. That didn’t happen with these. The bars are estimated to be 220 calories each but I never felt like I just ate a whole lump of food in my gut and the bacon also never felt greasy or heavy – something I worried about. The protein in these is perfect for distance events.

There are plenty of variations on the original recipe. In this video Allen shows a slightly different version:

The drawbacks? Well, mostly my fault and easy to correct. I crushed one bar in my pocket and it fell apart. (I had two stuffed in a pocket and two in a gas tank.) Some others were also fairly crumbly. Easy fix, make the rice so that it comes out a bit stickier, pack it together tighter, and place them somewhere they won’t get crushed. The other issue wasn’t with the bar but the foil I used. I used a fairly thin and weak foil which didn’t hold up well. Sometimes it tore in ways I didn’t intend or desire. This foil also seemed to “rub off” on the bars. I had a bit of aluminum oxide that looked like brake dust on one bar. Not wanting to supplement with aluminum I’ll probably be able to easily fix both issues by using a higher grade/quality of foil.  So, the only “issues” were largely my fault and easy to solve.

This wasn’t the only thing I ate on the ride. SDM has fewer calories so you eat more frequently than with other carb/electrolyte mixes. I was eating a gummie every 10-15 minutes (GU Chomps, Honey Stinger, Sharkies etc.) and the larger stuff on the hour. I alternated between a rice bar and Organic Honey Stinger Waffles. The waffles still work very well for me. They provide a sweet treat that I’ve digested well and had no problem with.

When we got back to the car I was fatigued, but I wasn’t exhausted.  I hadn’t changed anything other than the nutrition but I felt better after 102 miles (at a faster pace) than I did after 80 the week prior. This is only the second 100+ mile ride I've done. It’s been two full days, but I fell surprisingly well. Time will tell how SDM and real food work for me in the long run and under different conditions (e.g. Summer temps) but for now I’m sold. Time to try those bacon muffins and brown rice waffle sammies!

Tuesday, March 13, 2012

The antonym of "epic" - scouting mission

A full seven hours of saddle (sore?) time were on the training schedule. After some coordination earlier in the week Ben Welnak and I decided to meet up Sunday to scout the second half of his AntiEpic route. A added a bit extra to up the mileage and provide the hours I planned. A few unexpected mapping events made this “extra” unnecessary.

While I prepped the night before I managed to leave the house without a hat or sunglasses. As I left Boulder though, it was cloudy, sprinkled some and the temps dropped from 40 to the mid 30s. Crap! I had a really crappy pair of shades I purchased years ago that collect dust in the car. I upgraded last year because my eyes would always be tired and sometimes even sore after a long day using these. I only get one set of peepers and they’re worth it. Regardless, the craptastic truck stop shades would have to do for the day. The hat was provided courtesy of the Elizabeth, CO Wal-Mart women’s department (apparently men there don’t get cold ears). I honestly didn’t even think I would need a hat as the temps were supposed to be near 60. Crisis averted.

I met Ben at the Post Office in Kiowa, where we quickly kitted up and rolled out. A short jaunt down the pavement took us to the first of many miles of premium gravel. Heading North we both had cue sheets and I also had the route loaded to my Edge 500. The Garmin wasn't giving directions. I should have had a clue why when it said “You’re Finished” after I had just turned it on. I had loaded the course earlier that morning to make sure it was in the unit, and apparently that screwed things up somehow. Stopping the course and then selecting “Do Course” again fixed the issue. Too bad I didn't realize this till after 60 miles and our two navigation issues.

The first was completely missing a right turn. To be fair we didn’t really miss the turn – the road just wasn’t there. After a brief reroute we later saw the back end of the road (not as dirty as that sounds). What looked like a fine road on Google turned out to be a degraded farm service road which nobody had driven for years.  + a few miles.

Rolling into Deer Trail we scoped out the town. Long ago when, Deer Trail was a shipping point for grain the town held two banks, five    both of the gas stations and made a quick stop at the local watering hole/cafĂ© – The Brown Derby. Honestly, I would be surprised to see someone wearing a derby of any color in Deer Trail. Leaving the big city for the return leg, we realized Ben and I had routed different courses. We rolled south to scope his course which avoided backtracking up a hill (smart choice) and managed to completely miss Co Rd 47. How did we miss that, we just passed 42? Well, one side of the intersection is 42, the other side is 47. Oh, and 47 is a gated driveway after 50 yards. Back to Deer Trail and the backtrack route. + a few more miles

The route South was pretty great. There are far more hills in this section, but the road curves, there’s more interesting scenery and the surface was better. It was on this southern leg that I got the Garmin working again. It really does save a lot of time having the course loaded. All those seconds of stopping and looking at the cue card really add up. We had stopped in Deer Trail for a good while where we scouted the town and I refilled fluids, we probably stopped half a dozen times just for pictures and I made a few nature stops, but all in all only lost 30 minutes out of 7 hours.

On Not flying solo
I was glad for the company on the ride. Excepting races, all of my other long training rides have been solo. As Ben rightly opined, riding this far on gravel isn’t quite normal even for a cyclist. Ben has many more years of experience, training and about 4 billion watts of power on me. We rode a pretty quick pace all day and kept yo-yoing through the hills. I’d scream down only to see Ben catch and pass me (like I was standing still) on nearly every ascent. This guy was still sick, riding a 29er, hauling about 200oz of water and still he was powering up the hills in an insanely high gear. I swear he didn’t leave the big ring all day. Check out Ben's take on our ride HERE

Monday, March 5, 2012

Kiowa 808

Finally, got back out for an adventure ride. The temps warmed up to 50s and the sun was glorious all day. 

The name? I started in Kiowa, CO; 79.7 miles is close enough to call it 80; and the route was something of a figure 8. I planned the route aiming for around a 5 hour ride time and hoping to have some hills. In the end there was about 20% more elevation gain than the software predicted. Still it was good training, a great route, and I finished in 3 minutes shy of the ride time I predicted.  

I began right at noon in Kiowa, CO. This is the first time I’ve gone through Kiowa or Elizabeth, but both look like they have plenty of services and I admit that the pizza shops had me salivating. In any case, I quickly passed the first couple paved miles before hitting the dirt. This was thie first minor surprise. I had entered the route in the Garmin, and carried a cue sheet. The cue sheet read what I thought the Google map said – Maui road. The actual road name was far less pleasant sounding – Maul Road. Fortunately no mauling occurred on this route and I only had one unrestrainded dog chase 

I was however destined to have Johnny Cash join me for about 50 miles of the ride. He decided on Sam Hall for some reason (sadly I can't embed this one). It's far from my favorite Cash song - perhaps it stuck because the lyrics were so simple and I could focus on the riding. Or perhaps it's because Sam Hall was so much better than the alternative that occasionally came in my head - MC hammer. I don't know why, but the roads in Elbert County can get quite a bit of washboard. Those sections gave me the Hammer inspiration as I had quite a few bumps hit my rump

One of the highlights of the route was Co Rd 37. I hadn’t intentionally planned to include a minimum maintenance road, but I got one here. Honestly, I’d take more miles of 37 over the MC Hammer washboard. CR 37 was a bit soft in spots and there were sections where runoff made little artificial stream crossings, but all in all it was pretty tame. Bunny hopping the smaller streams made them something I looked forward to. I’m still not sure where the B-road is in the AntiEpic course, but if this is it I ain’t skeered.

Never seen this sign before but I like it! 
B-road fun!

 After 37 I wound my way down onto the Peyton Highway. This rural dirt road might be my favorite “highway” ever given that this section was unpaved. I passed a few folks on horses here and we chatted for a bit. They were really nice folks and the only people I chatted with on this ride. I will say though that I had far more friendly steering wheel waves than I usually receive. Beautiful scenery and friendly folk.

Unfortunately, Payton Hwy does become paved and I took it to Murphy Road for the bottom edge of my route. While paved, Murphy was actually slow going as I faced a headwind and it’s a deceptive climb for about seven miles. With that over I headed north and ended up back on gravel. Meridian becomes county line road at this interesting horse sculpture. It’s hard to tell but the mane is barbed wire.

Horse with barbed wire mane.

The next several miles along Kiowa Creek passed incredibly quickly – too quickly. The scenery there is great and I was actually surprised and a little disappointed when I found myself in Elbert. I had planned to refill one of my bottles at the convenience store in Elbert, but decided to pass as I had started hydrated and only just finished 2 of 3 bottles. In retrospect this was probably a mistake. I wasn’t really drinking enough on the ride. I finished fine, but probably could have finished faster and stronger, with a quicker recovery if I had hydrated more. I’ve been able to get away with this on these 4-5 hour rides, but I know it’s a poor plan and on anything longer I’ll be in trouble.

Church in Elbert. It's not leaning, I was on a slope and not paying attention.

Leaving Elbert and returning to the car took far longer than I expected. The day had gone so quickly already and for some reason I thought I was close to the end. In reality, I still had ¼ of the ride to go. I was rewarded with a screaming fast descent, but the final paved slog uphill to the car more than made up for it. It was on this last leg after Elbert that I felt my fatigue and underhydration.

I’ve got plenty of long training rides remaining where I’ll be playing with nutrition and hydration options. It’s a constant quest to find what works in this department. I’ve already determined that gels are not for me, but gummies work surprisingly well. I moved from Gatorade to Heed with some success, but recently decided to go half measure on the Heed and add additional electrolytes effectively reducing the carbs and increasing the electrolytes. This allows me to eat a greater percentage of my calories rather than drink them. I still love the waffles, but over the next few months I’ll also be playing with some of the recipes in Dr. Allen Lim’s book The Feed Zone which uses real foods. I’ve never liked the idea of relying on too much robot food, so if I can find something that works well for me I’m all for it.

Friday, March 2, 2012

Disc brakes: Gnothi Seauton

When I've gone to the Mosaic shop Aaron has mentioned an online article about the complications and potential dangers of using disc brakes for road bikes a couple times.  I finally found the original article as well as a follow-up.

The Articles
The original article opens with the author's cautionary tale of a dramatic crash that resulted from complete brake failure on a road descent. The author was on a disc equipped Moots, which is a very similar setup to what I now have. The original article moves from this story to a discussion with several manufacturers about using disc brakes on road bikes (Shimano, TRP, Magura, Hayes). The article includes a discussion of why brake failure occurs and the challenges of using disc brakes on a road bike vs a mountain bike.

The follow-up second article is purely a discussion with wheel and hub manufacturers (American Classic, DT Swiss, Rolf Prima, Easton, Zipp, Reynolds) about the challenges and opportunities of building disc brake capable road bike wheels including a discussion of rims, hubs and spoke changes. While this discussion is interesting as a preview, there's nothing too alarming. The first article is a different story.

I'm still in love with the new bike. I've done a few more rides where I've begun incorporating some of the local hills on a route called Olde Stage Road. Recently I clocked 54 mph on the descent and the idea of brake failure at that speed is unappealing to say the least. The main difference (on the surface) in road vs mountain bike braking appears to be higher speeds and longer descents. This main issue is one of heat dissipation.  I won't rehash the article, but will say that talk of boiling hydraulic fluid and warped rotors is a little alarming. While I do think the author made an effort to be impartial in the presentation, I feel that without a close critical read, it could easily come off as alarmist. Beginning this tale with a major failure, and  a serious injury sets this tone.

Misinterpretation of purpose
This article does not provide, nor was it intended to provide, a discussion of the merits of using disc bakes as compared to rim brakes, on road bikes. Such a discussion could have offered a balanced presentation of the strengths and weaknesses of each system. Of these four topics which could be discussed (the pros and cons of disc, the pros and cons of rim brakes) the article mostly focuses on the challenges of disc brakes. Unfortunately, many readers are not cautious consumers of information. Reading this article understanding the purpose as "hey these disc brakes are kinda new for use on the road and they're not perfect. Here's some stuff you may not know, but should" makes it a brilliant piece of timely work that I was happy to find. Just remember it's only one part of the road bike brake discussion.

Comments worth reading
Reading the comments (which I recommend in this case) shows that many did not take this interpretation - something I cannot fault the author for. Many others who offered their comments provided useful feedback and valuable information. While most comments sections of popular articles quickly devolve into flame wars or tangent discussions, this very long list of comments provides a window into varying experiences and a picture of rim brake limitations, and disc brake benefits, which the article itself lacks. This might be the only time I'll say that the comment section is just as valuable to read as the article itself.

Lessons learned
I'm quite happy to have the information this article provides as I did learn a few things that may impact upcoming rotor/wheel purchases. If you're considering disc brakes on a road bike, this article and the follow-up are worth a read. Just makes sure you also know the strengths and limitations of rim brakes as well so you can be best prepared to make your own informed opinion. Disc and rim brakes each have their strengths and limitations: neither system is perfect but either should work fine when set-up and used correctly. Here's my summary of what I've gathered:

  • Rim brakes work and disc brakes work, but both can and do fail. 
    • Disc brakes can overheat, glaze and warp rotors in the right conditions leading to brake failure. 
    • Rim brakes can overheat, glaze and explode tubes in the right conditions leading to brake failure. Rim brakes on carbon rims or in wet/snowy/frozen/muddy conditions provide extra challenges. 
  • Disc brakes are newer in use on the road and there are some engineering challenges that have yet to be perfected. 
    • This is not to say, however, that we're in the stone age here. Current mechanical sysems work just fine, but many companies seem committed to developing road disc technology and within the next few years we will likely see a rapid evolution in products that at the very least reduce weight and may improve performance. (cf the SRAM Red hydraulic line slated for release Summer 2012 and the many ideas being floated here)
    • Current weights are undeniably higher in a disc brake system. There's just no room for argument or debate here - the extra spokes, rotors and heavier calipers make the system heavier. BUT the new SRAM hydraulics and the very recently announced Shimano road and CX mechanical disc brakes are shedding weight quickly. (e.g. my BB7s weigh 220g each while Shimano claim their CX75 at 156g - no small drop)
  • Operator error can be a major factor leading to failure. 
    • Like rim brakes, disc brakes are more prone to failure when used in a constant manner (continuous hold) rather than intermittent (i.e. fluttering or brake-release-repeat). A little education and awareness goes a long way here.
  • Equipment choice is important, and so is knowing where you're riding.
    • Small (i.e. 140mm) weight weenie rotors (Ashima, KCNC, etc.) do a poor job at heat dissipation. Using them for a high speed descent from the Col du Tourmalet may not be the best choice at this time. A larger rotor (160) with greater surface and heat shedding ability (e.g. Shimano IceTech or Avid HSX) would be a better choice. 
    • Using small, weight weenie rotors for a long flat ride regardless of speed, in a CX race, or in a situation where frequent albeit brief braking is the norm (i.e. gravel racing), is probably fine. 
Shimano's new CX75

Will it impact my equipment choice or riding? Perhaps.
I'm currently running a 160 front and 140 rear rotor and both are in or near the weight weenie category. I have no worries about using these for most of my riding, but may purchase a set of rotors that are better at heat shedding for use on routes with long fast road descents. As far as how I use the brakes is concerned, I can guarantee you that I'll be thinking of how long I pull that lever on long descents. 

My current front brake setup