Q about something on the TdF riders bikes?

Question

During the highlights I watch, I can't help but notice that all bikes have a very small yellow thing underneath their left chainstay. If this something needed for timings, GPS or something?

Answer 1

I think you're right. It transmits heart rate, ect...

Answer 2

Up close pic of timing chip

http://www.cyclingnews.com/road/2007/tou...

Yes those are the timing chips. Supplied by the TDF.

http://www.engadget.com/2004/07/19/count...

What’s that Yellow Thing on Everyone’s Bike?

Last year, cycling fans watching the Tour de France wondered, “What’s that little yellow thing on the riders’ bikes?” “Is it the latest gadget that will help them go faster?” “Maybe it’s a GPS or telemetry sensor.”

The answer is the AMB Activ timing chip.

The official timekeepers of the Tour de France, MATSPORT, implemented the AMB Activ timing system at the 2004 Tour de France to provide live preliminary results to fans and the media. This was the first time a chip timing system had ever been used at the Tour.

With each rider having an Activ timing chip on their bike’s left chain stay, the Activ timing system automatically detects and times each rider. Since each chip emits a unique code, the Activ system automatically knows which rider went by. With MATSPORT’s complex wired and wireless networks, the Activ system feeds the data live back to the timing trailer located at the finish of each stage. MATSPORT’s timing software then compiles the times and splits of each rider into the General Classification (overall result based on each rider’s total course time.

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Not for heart rate, the only thing mounted there would be for cadence. But all riders don't use the same computer.

Answer 3

Mr. G, Carl may be right.   On the TV broadcasts, we occasionally get watts and heart rate readings on a select few riders.   There are lots of ways that could be transmitted, but I seem to remember commentary last year indicating that the "small yellow thing" was involved in the process (in addition to being a timing chip).

Answer 4

They are timing chips, with a unique identity code used to identify the rider. A radio signal is transmitted to the chip at the start and finish (the chip then responds by sending back a code) to accurately record start and finish times (sometimes on sportives, they are used elsewhere on the route, to catch cheaters!)

Every sportive event I have entered, uses them.

Carl - as a regular contributor, I am a little disappointed that you suggest a chip attached to the chainstay can measure heartrate????

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