Jul 21 2012

Tour de France Time Trial Bikes

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I see a lot of these dudes have non-circular chainwheels. I was under the impression that these things–which first appeared in the 1970s–had been debunked as failing to provide any advantage.

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28 comments

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1

Drugmonkey

July 21, 2012 at 4:03 pm (UTC -7) Link to this comment

You are wrong. Noncircular rings have ebbed and flowed but never gone away entirely. Bobby Julich, I think it was, rode them for everything towards the end of his career…
2

slc1

July 21, 2012 at 4:15 pm (UTC -7) Link to this comment

One of my bikes has oval chainwheels. I don’t know if it makes any difference or not.
3

Sili (I have no penis and I must jizz)

July 21, 2012 at 5:06 pm (UTC -7) Link to this comment

Never heard of those, but I recall some work done about a decade ago, showing the the weight advantage from using small chainwheels is more than eliminated by the increased friction.
4

dab

July 21, 2012 at 6:25 pm (UTC -7) Link to this comment

<< Twitter is that way <<
5

Cuttlefish

July 21, 2012 at 6:39 pm (UTC -7) Link to this comment

Given the money and research behind the top riders, if I see a particular rider in, say, the top ten, riding with an elliptical gear, I’m gonna assume they tested the fucke out of every possible configuration and this is what works for him.

Different riders have different cadences, different power strokes, etc. Armstrong’s turnover was very high compared to his competitors, for instance. It is entirely possible that it is more cost-effective to modify a gear than to re-train a rider’s form.

The trick is, a test of “circular vs elliptical” with all other variables held equal, ignores the fact that all other variables are not equal. The best chainwheel for you might not be the best for me.
6

davidmc

July 22, 2012 at 4:04 am (UTC -7) Link to this comment

It could be as much a psychological advantage as a physical one. As this NY Times piece explains.

http://www.nytimes.com/2012/07/23/sports/olympics/2012-olympics-how-britain-conquered-the-cycling-world.html?_r=1&pagewanted=all

There has been a couple of Documentaries on recetnly, one on Victoria Pendleton on the BBC and one on Bradley Wiggins on ITV, both have taken advantage of a top psychologist to help get the best out of both of them.

As far as i am concerned, Britains rise to domination in cycling, on the track and the road, is a direct result of building the velodrome in Manchester for the commonwealth games.
I just hope the billions spent on the olympics has the same effect.
7

davidmc

July 22, 2012 at 4:05 am (UTC -7) Link to this comment

ps COME ON CAV
8

reasonbeing

July 22, 2012 at 7:22 am (UTC -7) Link to this comment

They are supposed to eliminate the “dead spots” of the pedal stroke at 12 and 6 0′clock on the circular motion. With the amount of R&D those big teams put into their technology, I feel confident saying that there is something to it. They test all of that stuff in wind tunnels, with power meters, etc.
9

david

July 22, 2012 at 8:42 am (UTC -7) Link to this comment

PMID: 21266731
10

physioprof

July 22, 2012 at 12:54 pm (UTC -7) Link to this comment

ps COME ON CAV

He did it! Are Wiggins and Froome also gonna be on the Olympic road race team?
11

ChilternFixie

July 22, 2012 at 1:35 pm (UTC -7) Link to this comment

Their popularity comes and goes. The late Sheldon Brown gives a good explanation of their usefulness
12

Gvlgeologist, FCD

July 22, 2012 at 2:24 pm (UTC -7) Link to this comment

Somewhat OT, but at least bike-related: I had a pretty bad crash on my bike yesterday – went off a rail trail into gravel at 15-20 mph. Lots of cuts, scrapes, and bruises, and really sore today, but:

my helmet is shattered.

Not my head.

Please wear a helmet if you ride.
13

physioprof

July 22, 2012 at 2:28 pm (UTC -7) Link to this comment

Anecdotal helmet proselytization is not welcome on this blogge. The fact that your helmet broke doesn’t mean jacke fucken shitte about whether your head would have broke were you not wearing the helmet. There is a scientific literature on bicycle helmet efficacy. You should go check it out, with your skeptic hat firmly on your head.
14

David

July 22, 2012 at 2:30 pm (UTC -7) Link to this comment

Proff, the team is Wiggins, Froom, Miller, Stanard, with the sole aim of delivering Cavendish to the finish. Next Saturday
Wiggo is also doing the time trial, not sure about the others.
15

David

July 22, 2012 at 2:36 pm (UTC -7) Link to this comment

Info on the team and course here

http://www.britishcycling.org.uk/gbcyclingteam/article/oly20120705-gb-cyclingteam-Cycling-at-London-2012–Road-team-0

They go up a pretty steep hill nine times, so it wont be as easy as today.
16

davidmc

July 22, 2012 at 3:08 pm (UTC -7) Link to this comment

comments 14 aand 15 were by me not logged in, not to be confused with the other david
17

GvlGeologist

July 22, 2012 at 3:35 pm (UTC -7) Link to this comment

“Anecdotal helmet proselytization is not welcome on this blogge”

Good grief. My apologies. Won’t happen again.
18

Drugmonkey

July 23, 2012 at 7:14 am (UTC -7) Link to this comment

Bike helmets are awesome and have saved many people from becoming vegetables. Libertarians are, in fact, those who didn’t wear helmets as children and became frontally impaired as a result.
19

The40ozCuzie

July 23, 2012 at 7:45 am (UTC -7) Link to this comment

At this level, I’m starting to think psychology is critical. They used to talk about Lance that way, that it was more important to convince him that his bike gave him an edge, whether it did or not. I liked this quote about altitude training from a nytimes article on marathoner Ryan Hall.
——-
Scientists debate its effects. The variables that determine performance are complex, said Tim Noakes, an exercise physiologist at the University of Cape Town who served as an altitude expert for FIFA, soccer’s world governing body, at the 2010 World Cup in South Africa.

“If you look at the literature, some people benefit and some get worse, and the general result is no effect,” Noakes said of altitude training. The placebo effect, though, can be significant, Noakes said. He urges those who believe in altitude training to continue and those who are skeptical to skip it. At the elite level of marathon running, he said, psychology probably plays a more crucial role than physiology.
20

Hairy Chris, blah blah blah etc

July 23, 2012 at 8:56 am (UTC -7) Link to this comment

David @ 15

Yep, true. However both Cav and Wiggins have worked on their climbing. No shoe-in, for sure, but the team is immensely strong.

I was very impressed with Sagan at the TdF (Boassen Hagen, Goss, and a few others), but if Cav gets a lead out in any way close to how he did in the last 2 road stages he’ll be incredibly difficult to beat.
21

David

July 23, 2012 at 11:39 am (UTC -7) Link to this comment

Hairy Chris, Sagan future contender perhaps? One of my many worries, Cav climbs better, but possibly with less top end speed. The others will bury themselves to get him to the line and if its half as good a team performance as the world championships, that is, only 50 percent perfection , should be enough.
So why am i nervous?
Mens Road Race, FROM 10.45 AM, GMT
Everyone is growing sideburns
22

davidmc

July 23, 2012 at 11:41 am (UTC -7) Link to this comment

I agree with my unlogged in self at 21
with the addition of , if they arnt growing thier own sideburns , they are getting false ones.
23

Hairy Chris, blah blah blah etc

July 24, 2012 at 2:32 am (UTC -7) Link to this comment

Mm, all things being equal for a short or uphill sprint I’d rate Sagan (power), longer sprint Cav (endurance & experience). All things aren’t equal, though, so I hope that the team don’t screw up! It’s definitely a weird course, 9 short climbs & descents so the teams will really need to be on it.

As for sideburns, due to having a beard they are somewhat integrated already.
24

Hairy Chris, blah blah blah etc

July 24, 2012 at 2:38 am (UTC -7) Link to this comment

Oh, and for the time trial, Wiggins unless illness or accident…
25

davidmc

July 24, 2012 at 8:10 am (UTC -7) Link to this comment

Im going for team GeeB to, more or less, sweep the board, men and women, road and track.
26

beardedbeard

July 24, 2012 at 9:51 am (UTC -7) Link to this comment

I was under the impression that Box Hill was a fair bit of climbing and the teams are worried they will not even get their sprinters to the line to duke it out and the race will be won by some dirty climber.

On topic, sort of, I had the misfortune of riding a bio-pace on my winter commuter last year and I was really happy to sell that bike off the only way I found to get a cadence that was at all comfortable was to ride platforms and practically take my feet off the peddles at the top of the stroke. The pros of course are pros and could beat me senseless with their bio-pace rings but I don’t get the attraction.
27

davidmc

July 24, 2012 at 11:43 am (UTC -7) Link to this comment

Box Hill, 2.8 km in length, 140m high, max gradient 6%, aveage gradient 4%. A pimple! BUT! 9 times every 20 minues for 3 hours will make it hard to control, i think the pro’s should get up it ok. and nearly an hour to pull back any breakaways

Here are the estimated times

http://www.london2012.com/mm/Document/Documents/General/01/25/64/67/RoadRaceestimatedtimes_Neutral.pdf

Never tried one of those rings, my cycling days were more charity rides and country pubs and town pubs too, come to think of it.
28

karl

August 10, 2012 at 2:42 am (UTC -7) Link to this comment

I’ve got a bike with a oval chain ring and I hate it! I hear all the time that it doesn’t make any difference but I think it’s worse by a mile (hope you like the pun), I also find that my chain tends to slip off more often when the gears come out of true slightly.