While I was watching the Lance Chronicles the other day if I recall correctly, some of the footage of Lance’s time on his TT bike was not on flat ground but seemed to be somewhere in the mountains (probably around Seattle and the wind tunnel). This got me wondering, at what point would it make sense for the Lance and some of the other Tour riders to use a TT bike for the stage up Alpe D’Huez instead of a road bike?
My questions is: at what speed will the effect of aerodynamics on a TT bike overtake the effect of weight and compromised aerodynamics on a road bike on an 8% climb? From the information I have read, when Alpe d’Huez it at the end of a road stage the best climbers can climb it around 40 minutes. I wonder what time that would translate into when they can start “fresh” and only have that one climb to do? I am guessing that times up the Alpe will be in the 35 or 36 minute range and this will give them an average speed of about 25 kph (15 mph). I seem to remember somewhere that aerodynamics begins to become the most important factor at above 12 mph (I may be wrong on this).
I am wondering if anyone will use a TT bike for the stage up Alpe D’Huez?
On year in the early 90’s when they had a Mont Ventoux TT, a lot of riders used TT bikes for the early part of the stage before the real climbing and then switched bikes to road bikes with light wheels as soon as it got pretty steep. For Alpe d"huez, I would imagine that they will go for super light road bikes. This stage will be all about “power to weight”. It would be highly unlikely that any of these guys use there TT bikes as they will “gain weight”. I suspect that another reason would be that they will be more efficient climbing in a slack roadie position than jacked forward at 76 degrees (keep in mind the UCI 5 cm behind bb rule) given that they are riding slack every day for 6 hours.
I caught a few minutes of OLN over the weekend and they were showing off a very tricked out, custom made Colnago that was built for Levi Leipheimer to use for the L’Alp TT. They literally had the bike at the exact gram for the UCI weight restrictions. Anyway it was a pure road configuration so it looks like at least one guy will be riding that stage on a slack angle. This is going to be a very cool stage to watch!
Over the weekend I did an uphill TT in Wintergreen, Virginia and I’m glad I brought my road bike and not my TT bike. The climb might not have been Alpe D’Huez but it was still a tough 7 mile climb with sections inclined at 15-20%. TT bars offered no help but my 11-34 cassette in the back sure did. Check out the link http://www.wintergreenresort.com/activities/wintergreen_ascent.asp
Also, what types of cassettes do you think the top cyclists will use in the Alpe D’Huez TT? I bet we will see quite a few compact cranks.
I’ll be a lucky fellow this summer. I’ll be at Alpe d’Huez for the TT stage and plan to ride it the next day to see how lame I am compared to the pros ! Truthfully though, I think this stage might actually be more exciting to watch on the TV as being on the side of the mountain will only give us momentary glimpses of what happens on the whole mountain. I understand there is a grandstand with a one of those big video boards at the summit, but the likelihood of getting in there is near zero !
Kraig Willett, biketechreview, did a thorough analysis of this question using Chris Horner’s victory in a Redlands time trial and his choice of road bike or TT bike and how various factors would affect that choice. If you’re really interested in how to answer your question and what factors to consider, you should give it a read.
I imagine they will use light road bikes as well just because “that is how it is always been done on uphill time trials”. I was just wondering if anyone has actually thought about the science behind getting up the hill fastest and figured out the weight versus aerodynamics trade off. Depending upon the speed, climbing a hill may not always be about “power to weight”, if the speed is high enough aerodynamic drag will be a major issue as well. I just wonder at what speed that cross over occurs.
If I were competing on that stage I sure would want to know at exactly what speed I would be better suited on either bike (and I am sure the top guys do know this) and how that compares to the pace I expected to maintain. If roadies alway did things according to tradition, Greg Lemond would never have won that final time trial and intoduced aerobars to the European peloton.
Kraig Willett, biketechreview, did a thorough analysis of this question using Chris Horner’s victory in a Redlands time trial and his choice of road bike or TT bike and how various factors would affect that choice. If you’re really interested in how to answer your question and what factors to consider, you should give it a read.
Thanks - I will have to check it out.
I used to live in Charlottesville and did the Wintergreen Mountian ride in training once per month. I used my Trek 2300 setup for Triathlons. I parked down in Wintergreen and rode to Devils Nob. Easily hit 55 on the way back down!!
I try to respect the research Kraig does at his own expense that we benefit from. He does sell access to his research at very reasonable rates. Some of his research is published and is part of the public record. I prefer to defer to permit Kraig to supply links to the research he chooses to share free gratis.
A link to this article was posted on this forum in the recent past (couple of months). Do a search on Redlands or Redlands Chris Horner and you should be able to turn it up. Or Google it.
"I try to respect the research Kraig does at his own expense that we benefit from. He does sell access to his research at very reasonable rates. Some of his research is published and is part of the public record. I prefer to defer to permit Kraig to supply links to the research he chooses to share free gratis. "
As a subscriber to Kraig’s site I respect his work and don’t refer to his results or give hints about his conclusions; however, what could possibly be wrong with providing a link to an article he has decided to make available to the public? It seems like a good form of advertising for his work and by your logic, Kraig would have to monitor every board and discussion group to make people aware of his work. So here’s the link to the Redlands article (note it’s from Bike.com):
I seriously doubt you will see compact cranks. If you do, it will be for weight savings, not low gears. These guys don’t need low gears. And the weight savings of a compact setup are pretty minimal.
I’d guess that a typical low gear might be 39/23 or 39/21 for the contenders. Which doesn’t mean they will actually use the largest cogs either. Some of the domestiques & sprinters might use lower gears, after all they’ll essentially be riding the stage, not racing it.
I’d guess the only aero equipment you’ll see will be skinsuits and deep cf spoked wheels, such as zipp 404, ada, lightweight. No aero bars or TT frames. This is a classic uphill TT and much harder and slower than the Redlands TT that Kraig Willet analyzed.
I agree, I think Armstrong used a 39-22 in 2001 - at the end of a long day of climbing. You may see some clip-ons as there is a big ring section toward the top. Speeds might increase for a length of time for them to be effective. Sticking with 2001, Armstrong used clip-ons in that uphill time trial the day after the Alpe, but it wasn’t nearly as steep either. Equipment choice should be interesting. That’s going to be a great day of bike racing - I can’t remember a more anticipated stage for the Tour in recent memory.
Oh, you’ll see compact cranks, aerobars, everything under the sun. This is actually one thing we’re doing at the MIT windtunnel this week with CSC, testing different bike and rider set-ups for Alpe d’Huez. Pretty interesting stuff. Rider position is much more interesting for this stage than for the flat TT, since there is a much more complex balance between power output and position. But I don’t want to say too much more about it, just wait until July.
Over the weekend I did an uphill TT in Wintergreen, Virginia and I’m glad I brought my road bike and not my TT bike. The climb might not have been Alpe D’Huez but it was still a tough 7 mile climb with sections inclined at 15-20%. Dave-I hate to be the one to burst the bubble but 2500ft of climbing in 7 odd miles isn’t 15-20% it’s 15-20 degrees - very different proposition! The course is about 7% overall. If you want to see what 15-20% looks like ride the L’Angliru in Spain (Usually on La Vuelta!) 1570m in 12.9km (Thats 5150ft in 8 miles) with sections @ 23.6% max (V. scary!) even pros use a 27 on that - I might go for FSA compact with 27 on the back (or a triple with a 27 - or a mountain bike!)
I believe at last year’s Vuelta, Roberto Herras used a road configuration on the uphill TT stage to make up over a minute and win the overall race. My guess is that while you can generate enough speed in a slack riding positon or out of the saddle climbing very steep mountains, you cannot generate that same speed in an areo position, or at least most riders can’t. Thus most folks will ride the lightest possible road bike they can build.