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    Average ascent speed

    Today there are serious climbs 1 of close to 7% and one of near 9!!Anyone tell me what kinfd of speeds going up?And do they hit 60MPH going down as the commentator says?

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    Senior Member slims_s's Avatar
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    Let's see... I'm taking Alpe d'Huez as the example, it is 13.8km at 7.9% average. Best time last year was 41' 21" (0.68916 hours) by Samu Sanchez, so the average speed was ~20km/h... holy s**t.
    Pantani's ride on 1997, 37' 35", ~22km/h, hmmm... juicy

    Source: http://en.wikipedia.org/wiki/Alpe_d%27Huez

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    Senior Member PatrickGSR94's Avatar
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    I really think some of those commentators have gotten MPH and KPH confused on some occasions.
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    Travelling hopefully chasm54's Avatar
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    Quote Originally Posted by PatrickGSR94 View Post
    I really think some of those commentators have gotten MPH and KPH confused on some occasions.
    No, they really haven't. It is quite common for some of the better descenders to exceed 100 kph/60mph. Often these guys are the sprinters in the grupetto who seek to make up time on the descents to stay within the time limits. Sean Kelly, back in the eighties, was clocked by one of the motorbikes as descending at 124 kph while chasing to get back on. Personally I think that is implausible - motorbike speedometers aren't always accurate - but it's pretty clear he was going ******** quick.

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    Senior Member colombo357's Avatar
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    I've rarely hit 50mph. It takes a steep, straight road with no headwind to reach that speed.

    60mph would probably require a 1000 ft stretch of straight, 20% gradient road and possibly a tailwind.
    "I just googled triple crank set and i see what your saying. this bike has 9 of those "cranksets".
    "They are showing [the TDF of Versus] at 5 different times in the day. It doesn't say which one is the live one."

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    Senior Member Keith99's Avatar
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    From waht I remember the commentators are technically accurate but very misleading when it comes to decent speeds.

    Riders can easily reach 60 MPH. But this often gets said when they are on twisty turny narrow roads. They don't even come close there. But there are some decents that cut across the face and are pretty long and straight. For a rider trying to catch a group 60 MPH on such a section seems reasonable.
    Perish any man who suspects that these men either did or suffered anything unseemly.

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    Riding like its 1990 thenomad's Avatar
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    Speaking if ascent speeds... I watched the Tour of California on a stretch of mountain road about 8% and I think the speed they came up officially topped out at "!*&$@-ing FAST!!
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    I take what Phil and Paul say with a ~5 mph grain of salt, but 60 mph is absolutely possible on a straighter section of a steep European road. Also, Phil and Paul ALWAYS say "reaching speeds IN EXCESS OF ______" when they don't really mean it. Why are they saying they're exceeding "45-50 mph"? If you're going to give a range, just say they're exceeding 50 mph. Saying they're exceeding 3 mph is an equally, or more true statement. Right?

    Spinning a 53x11 gear at 120 rpm will put you at 46.4 mph. Pros can efficiently spin faster than that for short periods of time, but there's nothing about being a pro that alters the laws of gravity, wind resistance, and general physics on a straight, downhill section of road. Even guys like Cancellara, or heavy sprinters can't pedal their bike up to 60 mph, because they can't pedal efficiently at 200+ rpm, or perhaps it just makes more sense to get aero, use no energy, and still go 55 mph. Point being, physics does everything over 50 mph or so, and the rider doesn't control the conditions outside of aerodynamics (the "tuck", wheels, frame, etc.), mass, and wind resistance (getting behind a motorcycle or something).

    The fastest I've been on a bike is 59.9 mph, down a ~9% grade, with a stout tailwind. I weigh more than most pros at 165-170, and my bike weighs about 10 pounds more than theirs does on a mountain stage.

    For more info, check out the Garmin Connect page for the pro team, and look at the max speeds on the left. These are often glitchy, and guys forget to turn them off after bikes are loaded on vehicles, etc., but it'll give you a good idea of how fast they go. http://connect.garmin.com/teamGarmin
    Last edited by Kind of Blued; 07-13-12 at 11:07 AM.

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    Senior Member reef58's Avatar
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    I was timing the kilos on a flat stage and they were doing a kilometer in around 53 seconds that is somewhere around 67 to 68 KPH, and this was a flat stage. When the sprint was on they probably picked up at least 5 more KPH. So I don't think it is unreasonable for them to do 100kph downhill.

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    Amateur riding solo not in a race, 83kph, 51mph.

    http://www.youtube.com/watch?v=kSoE5...ailpage#t=582s

    http://youtu.be/0tFpNsZXWgc - the 100kph tdf video,

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    Senior Member colombo357's Avatar
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    Quote Originally Posted by reef58 View Post
    So I don't think it is unreasonable for them to do 100kph downhill.
    Required power increases exponentially with speed and wind resistance.

    A rider hits 60mph on the steepest, straightest, longest descents only. It is very much unreasonable to expect them to even hit 50mph on many of these descents.
    "I just googled triple crank set and i see what your saying. this bike has 9 of those "cranksets".
    "They are showing [the TDF of Versus] at 5 different times in the day. It doesn't say which one is the live one."

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    Senior Member reef58's Avatar
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    Keep in mind I am not saying the average descent speed is 100kph, but rather they can hit those speeds. I have done 50mph myself. It was scary as heck. I come from flatlands and am not a good descender.

    Quote Originally Posted by colombo357 View Post
    Required power increases exponentially with speed and wind resistance.

    A rider hits 60mph on the steepest, straightest, longest descents only. It is very much unreasonable to expect them to even hit 50mph on many of these descents.

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    Senior Member PatrickGSR94's Avatar
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    I was up to nearly 30 on a short, relatively winding descent last weekend, and that scared me pretty good. I had to get on those brakes coming around a curve at the bottom. I guess I'm still chicken at leaning into the curve, but I had visions of my tires sliding out from under me, and me going down on asphalt at 30 in shorts and a t-shirt would have made for a sucky day.
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    Quote Originally Posted by reef58 View Post
    I was timing the kilos on a flat stage and they were doing a kilometer in around 53 seconds that is somewhere around 67 to 68 KPH, and this was a flat stage. When the sprint was on they probably picked up at least 5 more KPH. So I don't think it is unreasonable for them to do 100kph downhill.
    Just because a sprinter can hit 45 mph on a flat, doesn't mean he can hit 60 mph on a downhill by up-shifting and pedaling at the same speed. He's already in his biggest gear at 45 mph. As I mentioned above, going 60 mph is dependent upon the descent, or the laws of physics, not the rider's ability.

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    Quote Originally Posted by colombo357 View Post
    Required power increases exponentially with speed and wind resistance.

    A rider hits 60mph on the steepest, straightest, longest descents only. It is very much unreasonable to expect them to even hit 50mph on many of these descents.
    I have hit 51mph on descents in Florida while others were pulling slowly away from me. It is not at all unreasonable to do 50mph on descents in the mountains. It is probably a more reasonable statement that it is unreasonable to not hit 50mph on many mountain descents. I have trained in northern Georgia & ridden the descents very conservatively having to stay on the brakes in order to stay below 50.

  16. #16
    Team Water Andy_K's Avatar
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    I coasted from a dead stop to 38.5 mph on a quarter mile of 8-10% descent this morning. I've gone as fast as 45mph coasting on a longer descent before I got nervous and started braking. Of course I weigh a bit more than your average TdF rider (and by 'a bit' I mean 50-60 pounds), so gravity helps me more.

    It's true that they won't be able to move the bike much faster than 50 just by pedalling, but if they pedal up to 50 mph and still have some slope in front of them it's all a matter of gravity, aerodynamics and terminal velocity. I don't see why 60 mph wouldn't be reachable.
    Last edited by Andy_K; 07-13-12 at 02:55 PM.

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    Team Water Andy_K's Avatar
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    Incidentally, using the defaults for air density, frontal area and drag coefficient with a 15% slope and zero available power (assuming the gears are spun out), the model at Analytic Cycling suggests a terminal velocity right around 60 mph for a 75 kg/165 pound rider, but dropping to ~55 mph for a 65 kg/143 pound rider, either of which would be reached within about a minute of coasting from a starting speed of 45 mph on a 15% slope.

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    starting pistol means war YMCA's Avatar
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    The back side of the Galibier is easy to reach 60mph.
    And yes the commentators exaggerate often, but the speeds are close enough to scare the bejeezus out of the average Joe.
    Especially rolling six wide at 70kph down long shallow grades

  19. #19
    don't try this at home. rm -rf's Avatar
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    Downhill
    Here's a youtube link with 100 kph showing on the camera motorcycle as two riders pass the motorcycle. See 0:28 showing the speedometer. This is the downhill after the Cormet de Roselend climb.

    A Strava ride showing the climb and downhill. It's near the 40 mile mark (hover on the elevation graph to see the climb names). But the leaders on Strava only did 34 mph average downhill. There's a couple of 8-10% grades in the middle--that's probably where the video was shot?

    Climbs
    VAM (altitude gain in meters per hour) is a good way to compare climbs that are different grades.

    Here's the strava climb for Alpe d'Huez with strava members posting their climbs. The fastest is at a VAM of 1386, that's 1386 vertical meters per hour. Armstrong and Pantini did about 1800 (says wikipedia). On a good day, I'm at about 650....

    VAM 1800 = 5900 feet/hr
    VAM 1350 = 4400 feet/hr
    VAM 650 = 2100 feet/hr
    Last edited by rm -rf; 07-13-12 at 04:20 PM.

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    Has coddling tendencies. KiddSisko's Avatar
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    On a normal road frame and non-aero wheels, I've topped 50mph on a stretch of road with an 8% gradient. And that's in a drop position, head and shoulders lowered with knees gripping the top tube. Pros riding bikes speedier than mine, who adopt extreme tuck positions minimize their drag even more, I can see how they surpass 60.
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  22. #22
    Beer >> Sanity bikerjp's Avatar
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    I'm 200lbs so gravity is my friend on the downhill side. I hit 52mph once on a section around 10-12% and I was not in a tuck - just on the hoods. Saw my speed and said holy **it and started to slow down. I don't let myself go that fast anymore. Some stupid squirrel (or driver) and I'd be in a world of hurt.
    Climbs like a stone, descends like two...

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    Has coddling tendencies. KiddSisko's Avatar
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    Video of a descent of Empire Pass in UT, reaching speeds of just shy of 70mph. Bike is a Blue Competition AC1, which is their road aero frame. Rider is one of their official reps, so even though there's no speedo overlay, we're gonna have to take his word about the top speed. Sure looks near 70!

    Empire Pass is a near 5 mile descent of 1800 feet, with a short uptick section in the middle. The fast section is the lower half - minute 7. Gotta be +/- 10% gradient on that stretch.
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    Quote Originally Posted by trek330 View Post
    Today there are serious climbs 1 of close to 7% and one of near 9!!Anyone tell me what kinfd of speeds going up?And do they hit 60MPH going down as the commentator says?
    The exact speeds that the elite pros attain climbing and descending are pretty fast compared to us mere mortals. Various things come into play but I would think that on a 7% grade the best climbers would be going around 15-16 MPH. This depends a lot on if it is the only steep hill or one of five major mountains on a long stage. Even on a long steep stage with multiple big mountains they will still maintain a 23-25 mph average. And the times spent going downhill are less because of the increased speed. So climbing speeds are faster than most people would believe. At the tour of Utah which went by my house on a climbing three circuit loop I estimated the time it would take the peloton to come by my house so I could go out to see them go by. It was a hilly climbing section for about five to six miles. They completely blew me away at how fast they are climbing. Especially on hills like 5% grades. Generally they are going uphill about 2-3 times faster then an average fit biker can go up the same hill in low gears on a mountain bike.

    On descents the quality of the road and how sharp the turns are have a big effect but 45-50 mph is common on most descents with the fastest speeds ever attained in ideal conditions over 70 mph. This was probably a very steep long straight descent with a significant tail wind.
    Last edited by Hezz; 07-15-12 at 11:22 PM.

  25. #25
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    Quote Originally Posted by slims_s View Post
    Let's see... I'm taking Alpe d'Huez as the example, it is 13.8km at 7.9% average. Best time last year was 41' 21" (0.68916 hours) by Samu Sanchez, so the average speed was ~20km/h... holy s**t.
    Pantani's ride on 1997, 37' 35", ~22km/h, hmmm... juicy

    Source: http://en.wikipedia.org/wiki/Alpe_d%27Huez
    Meh!! Many on the 41 can easily match that speed. Just ask.

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