Charlie Alliston, of Trothy Road, Bermondsey, was 18 when he allegedly hit Kim Briggs while going 20mph in central London in February 2016.
Mrs Briggs, 44, suffered brain injuries, including two skull fractures and died in hospital days later.
In what is believed to be a legal first, Mr Alliston, now 20, is on trial for manslaughter, which he denies.
He also denies causing bodily harm by wanton or furious driving.
HR consultant Mrs Briggs, of Lewisham, south London, had been on her lunch break when the crash happened.
The jury heard Alliston had been riding a "fixie" - a fixed wheel track bicycle with no front brake used by track racing cyclists - which is not legal on the road without modification.
A few days after the incident in Old Street, Shoreditch, Mr Alliston posted a comment online, claiming he had tried to warn Mrs Briggs but that she had "ignored me" and "stopped dead" in his path, the court heard.
The jury was told he wrote: "I feel bad due to the seriousness of her injuries but I can put my hand up and say this is not my fault."
On the forum he described how their heads collided and hers "ricocheted" into his, the trial heard.
He wrote: "It is a pretty serious incident so I won't bother saying she deserved it. It was her fault but she did not deserve it."
He went on to claim in the forum Mrs Briggs had been on her mobile phone at the time of the incident, the court heard.
Jurors at the Old Bailey were shown CCTV footage of the collision on 12 February and were told the defendant had been riding a black PlanetX carbon frame fixed rear pedal cycle.
That type of bike is more commonly seen racing at the Olympic velodrome, jurors were told.
If Mr Alliston had been riding a bike with proper brakes, he would have been able to avoid the collision with Mrs Briggs, prosecutor Duncan Penny QC said.
The trial continues.
A cyclist who knocked over and killed a woman posted on online forums the crash was "her fault", the Old Bailey heard.