I have been streaming the stuff I want to watch from my PC to my Chromecast from the list here ->
http://www.bbc.co.uk/sport/olympics/rio-2016/schedule I got sick of the BBC swapping and changing between sports all the time and this way I can see the whole event without interruptions.
You can watch live or watch after they have finished, the womens race is here ->
http://www.bbc.co.uk/sport/live/olympics/36599526 just grab the slider at the bottom of the video and pull it all the way to the left and it goes back to the beginning of the race.
Just becareful where you look before you reset the video incase it shows you the results.