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Discussion Starter · #1 ·
What is the small, yellow part hanging down from each riders chainstay on the non-drive side? Is it for telemetry back to the team car? GPS for the organziers and TV crews to determine where each rider is? A timing chip like running race organizers use? Every rider, regardless of team, seems to have the exact same thing. I've seen it in a number of different stages.

Apologies in advance if this has been asked and answered. My searches through prior posts were fruitless...
 

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ilan said:
It's to place riders electronically at the finish. They are all exactly the same distance from the front end of the bike which is the point where rules specify that a rider crosses the finish line. I suppose it assumes that riders will finish with their bikes roughly perpendicular to the finish line as opposed to say this: http://www.youtube.com/watch?v=eOkgbZ6kJeo

-ilan
A bike with unusual chain stays may have the device moved/mounted elsewhere.
 

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In another thread, I posted that it would be easy to score riders in the Tour on their actual accurate times using these GPS transponders..

How different would the results be if each rider was scored on his actual time rather than this odd-ball (but traditional) method of giving everyone in a 'cluster' of riders the same time?

When the margin is just a single second between the leader and second place and the top ten are within seconds of each other, would it not be interesting to see what times they might get if they were scored as they actually cross?

The chase group yesterday, they all got 'same time' but they were spread over about 30 seconds...just dribbling in...They probably wouldn't 'dribble' like that if each nano-second was scored, they would keep racing the whole stage, right?

Don Hanson
 

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Gnarly 928 said:
In another thread, I posted that it would be easy to score riders in the Tour on their actual accurate times using these GPS transponders..

How different would the results be if each rider was scored on his actual time rather than this odd-ball (but traditional) method of giving everyone in a 'cluster' of riders the same time?

When the margin is just a single second between the leader and second place and the top ten are within seconds of each other, would it not be interesting to see what times they might get if they were scored as they actually cross?

The chase group yesterday, they all got 'same time' but they were spread over about 30 seconds...just dribbling in...They probably wouldn't 'dribble' like that if each nano-second was scored, they would keep racing the whole stage, right?

Don Hanson
I think it would be too dangerous.
 

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Discussion Starter · #10 ·
I finally found a picture of one (from last year's tour).

I also found an old article on the timing chips (circa 2004).
The AMB Activ system works like this: Each bike starting the tour carries a small, yellow, battery-powered transponder. Fixed to the frame exactly 1.2 meters behind the leading edge of the front tire on the left chainstay, the transponder emits a seven-digit identification code via a process called "magnetic induction" to a detection loop taped across the road surface.
 

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There's actually a strong electromagnet in the device. Combined with the secret solid steel layer implanted beneath french roads, the frenchies can slow down riders that aren't french. The magnet needed to actually let a french rider win would be as big as a bike itself though. Or a huge advance in magnets will be needed.
 
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