Start time is 6 p.m. near the south entrance to the light festival. The only site I could find promoting the event is

http://www.bicyclekitchen.com/

Last year's ride via a dedicated lane through the lights was a casual/cool time, but a disappointing turnout. If traffic delays kept you away from the light festival in past years, here's an opportunity to avoid the bumper to bumper traffic and enjoy the lights at an easy pace.