While Chris Froome alleged that urine was thrown at him during this year 's race .
Fans are occasionally aggressive with riders , any kind of violence or crowd trouble is rare at races , with most fans there to cheer all the riders .
While Chris Froome alleged that urine was thrown at him during this year 's race , and fans are occasionally aggressive with riders , any kind of violence or crowd trouble is rare at races , with most fans there to cheer all the riders .