Wednesday, November 7, 2007

Q&A: Calculating the hour record distance

Hey Jim,
I was watching a movie the other night about the riders trying for the 1
hour record, and it posed a question. How do they so accurately calculate
the exact distance traveled when the 1 hour is up. The distance is
calculated down to 1/1000th of a mile. The riders are on a circular track,
and obviously complete the 1 hour at someplace other than the exact
completion of a lap. Can you help me out here.

Hi Jack,
You might have been watching The Flying Scotsman. If so, I enjoyed that
movie though they didn't capture how amazing Obree's accomplishments were in
my opinion.

In any case, I'm definitely not a track expert or a cycling official, the
guys who are charged with measuring records, however, I believe official
racing tracks are usually 250 meters long so since they know the exact
distance of the track they just need to know where the rider is on the track
when the hour ends and it should be a relatively simple matter to calculate
the distance ridden.

The track is essentially a 250-meter yardstick and when the hour ends the
rider's position is marked on the track and they can then count laps, add
them up and then add whatever additional distance he/she did on the last
lap. I believe the track is probably marked with gradations for accuracy,
too, though I don't know this for a fact. It's possible they use one of
those little walking wheel measuring devices to calculate the distance on
the last lap, too. It's probably something like this.

Perhaps you'll find an explanation on Wikipedia's page on hour records here:


1 comment:

Anonymous said...

The establishment of a record over a distance in a given time, may be the subject of a calculation in order to determine
the exact performance as mentioned below:
In the case of calculating distances travelled in a given time, for example the record for the hour, the candidate attempting
the record must, when the time has expired, finish the additional lap. The time for the last lap makes it possible to
determine, by means of the calculation, the average distance travelled.
D = (LPi x TC) + DiC
DiC = LPi x TRC
In which:
D: distance travelled in the hour
DiC: additional distance
LPi: track length
TTC: additional-lap time
TRC: time still to run at the start of the last lap
TC: number of complete laps before the last lap
The distance travelled is rounded down to the nearest metre. The record cannot be beaten by less than one metre.
As a function of the average time per lap of the track by the candidate attempting the record, the timekeeper must be
ready to trigger the bell announcing the last lap when the time still to run is less than the average time achieved for a
lap of the track.
The end of the attempt is announced by two pistol shots when the rider crosses the finish line after the time envisaged
has expired.
If, between the expiry of the time indicating the end of the attempt and the end of the last lap, an unforeseen incident,
puncture, fall, etc. does not enable the complete lap to be finished, it is the time for the previous lap that would be used
to calculate the additional distance travelled.
For any record attempt, the blue-band part must be rendered unusable by means of the fitting of beading 0.50 m long
and 0.08 m thick placed at the bends, every 5 metres.
A record broken on the same day (by the same rider) is not ratified.
A record cannot be broken by a distance of under one metre.

From document :