His mother, Nancy Larson, Thursday said the train her son, Kyle, regularly took from Manhasset had been canceled, so he took a later one.
According to the police, Larson was riding south on Union Square West, a few blocks from the university, around 11:15 a.m. when he lost control, fell and was hit by a 2004 Mitsubishi delivery box truck also traveling south on Union Square West.
There is no criminality suspected, the police said, but they want to question a bicyclist seen near the site of the accident.
In the days since Larson, 20, died, his mother said she has heard from a handful of his friends who told her about how he helped them through challenging times.
"People need help along the way sometimes, and that's what he'd be there to do, and they helped him," Nancy Larson said outside of her home in Manhasset Thursday morning.
Larson was a deft skateboarder, she said, and a talented musician. When he was at Manhasset High School, where he graduated in 2010, he was the drum major of the marching band. He played for the jazz band -- mastering saxophone and clarinet -- and sang with the Kinsmen, an a capella group.
Mark van Schenkhof, Larson's high school chorus teacher, remembered him as "incredibly dedicated."
He said he recruited Larson, then in 10th grade, to the chorus and the Kinsmen, right as the group was scheduled to perform upstate in Rochester.
"We were short a tenor, and he came to me and asked to try out," said van Schenkhof, of Port Washington. "I told him I didn't think he could learn all the music in two weeks, but he did."
He described Larson as hardworking. For practice or a performance, he was often the first one to arrive and the last to leave.
"And every time I picked music, he'd ask for something more difficult," van Schenkhof said.
Nancy Larson said her son had plans to travel West. "He loved Utah."
He also dreamed of studying overseas for a semester, she said.
Nancy Larson held up a black shirt that read, "To Write Love on Her Arms," paraphernalia from the nonprofit group of the same name, which its website says "is dedicated to presenting hope and finding help for people struggling with depression, addiction, self-injury and suicide."
She urged well-wishers to contribute to the group, citing Kyle's experience helping at-risk youth; some of them were his friends, some strangers.
"I'm learning about what he tried to do," Nancy Larson said, "from a lot of kids who have struggled themselves. He reached out to them."
On the website for the Kinsmen, words from the poem "Ode of Remembrance," are dedicated to Kyle Larson:
"They shall grow not old, as we that are left grow old:
Age shall not weary them, nor the years condemn.
At the going down of the sun and in the morning,
We will remember them."
With Gary Dymski