Great Britain's Mark Colbourne won the gold medal in the C1 3km individual pursuit at the Paralympic Games.
Colbourne, who won silver in the C1-2-3 one-kilometre time-trial on day one, clocked a world record of three minutes 53.881 seconds to triumph, with China's Li Zhang Yu second.
A distraught Jody Cundy protested and boos rang around the London 2012 velodrome after the 2008 Paralympic champion was denied a restart in the men's C4/5 1km time-trial. After Sarah Storey's triumph on day one, Cundy, another swimmer-turned-cyclist, was seeking his third Paralympic cycling title and sixth in all.
Cundy, a lower leg amputee and C4 rider, had a problem at the start and commissaires ruled he could not restart, despite coach Chris Furber's pleas. Officials argued the first start was down to rider error, not an equipment failure.
Alfonso Cabello finished in a C5 world record of 1:05.947 to claim gold with world champion Jon-Allan Butterworth, who lost his left arm while serving in Iraq with the RAF in 2007, taking silver in 1:05.985, 0.038 behind the Spaniard. Bronze went to China's Ji Xiaofei.
Butterworth's time was beneath his previous best, the world record set in Los Angeles in February.
Both Britons were world champions in their respective classes entering the event, which was factored due to mixing classes, but neither came away with Paralympic gold in their home Games.
Meanwhile gold medallist Colbourne felt his race went exactly to plan and he told Channel 4: "With this type of race you have to take your mind off who you are racing against. If I go flat out with six or seven laps gone I fill up with lactic acid and struggle for the later laps.
"We trained so that I could sustain a Bradley Wiggins-style pace from start to finish. Our plan worked. I had this dream two years ago along with Neil Smith from Disability Sport Wales. We are here today, aren't we? I keep pinching myself.
"I want to dedicate this gold to my late father and my mother who is in the crowd, and to my daughter."