Venera Minakhmetova died when she was struck by lorry at Bow Roundabout, on Wednesday.
The Russian, who had been on the Cycle Superhighway 2 (CS2) just before the collision, was the fourth of five cyclists to die in London in nine days.
Her sister Dina said: "If you know something, if you witnessed it, please come forward and contact police."
She also thanked people for their support following her sister's death.
Ms Minakhmetova had worked at London-based Edelau and investment bank Merrill Lynch and was living in the Bethnal Green area to develop her financial services business.
So far this year, 13 cyclists have been killed, eight of which have involved HGVs.
The leader of Southwark Council, Peter John, has called for HGVs to be banned during rush hour to protect cyclists.
Currently, the movement of HGVs are restricted in London between 21:00 and 0700 on weekdays, and between 13:00 on Saturdays through to 07:00 on Mondays.
Speaking to BBC Sunday Politics London Ben Plowden, of Transport for London, said the Olympics showed it was possible to achieve a very significant change in when and how deliveries take place.
"Something like a fifth of freight activity moved out of the busiest times in the day and that was because we worked closely with the boroughs and the councils, the freight industry and the supermarkets and other people to make that happen," he said.
"So what that shows is you can make a big change, the question is how do you make that part of everyday life rather than a one-off thing for the Olympics?"
Catherine West, head of transport on London Councils, said a balance was needed so that Londoners could get a good night's sleep.
"A lot of people live on busy roads and they live above shops. We just have to be mindful that a lorry delivery at 4am may not be great for residents," she said.
The sister of a cyclist who was killed in east London last week has urged witnesses to contact police.