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.
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
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: