<P> A team time trial (TTT) is a race against the clock in which each team rides alone . The time is that of the fifth rider of each team: riders more than a bike - length behind their team's fifth rider are awarded their own times . The TTT has been criticised for favouring strong teams and handicapping strong riders in weak teams . The prologue stage in 1971 was a team time trial . </P> <P> Riders completing a stage may be eliminated if their time exceeds the time limit for the stage . The limit is defined as the winner's time plus a percentage, which depends on the type of stage and the winner's average speed . The time limit can be extended or the elimination can be waived if more than 20% of riders exceed the limit or for other reasons such as collisions or foul weather . For example, for a stage classed as "Coefficient 1: Stages with no particular difficulty", the time limit is the winner's time plus 3% for an average speed of up to 36 km / h, increasing in 8 steps to 11% for a speed of over 50 km / h, while on a "Coefficient 5: Very difficult short stages" it varies from 11% (up to 30 km / h) to 22% (over 40 km / h). </P> <P> The race has finished since 1975 with laps of the Champs - Élysées . This stage rarely challenges the leader because it is flat and the leader usually has too much time in hand to be denied . But in 1987, Pedro Delgado broke away on the Champs to challenge the 40 - second lead held by Stephen Roche . He and Roche finished in the peloton and Roche won the Tour . In modern times, there tends to be a gentlemen's agreement: while the points classification is still contended if possible, the overall classification is not fought over; because of this, it is not uncommon for the de facto winner of the overall classification to ride into Paris holding a glass of champagne . </P> <P> In 1989 the last stage was a time trial . Greg LeMond overtook Laurent Fignon to win by eight seconds, the closest margin in the Tour's history . </P>

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