When she bounced the idea off one of her regular customers, she had no idea he was in the business of fund-raising. “I told her I thought it was a great idea, but she could think on a bigger scale,” said Gregory Cohen, a Kensington resident who helps run Cause Effective, a fund-raising company. He donated his time and knowledge and introduced Ms. Alfonzo to ioby, a community crowdfunding organization that could provide non-profit status and handle tax-deductible donations.

But that was just one of the obstacles.

“This is not like putting a bike under the Christmas tree,” Mr. Cohen said. “You have to find a kid for whom an adaptable bike is suitable and make sure they have someone who is willing to coach them and stay with it.”

He and Ms. Alfonzo reached out to physical therapists in local schools, who had a list of children with disabilities waiting for the custom bicycles. “We are looking for parents who really want to do this with their kids,” said Ms. Alfonzo. “We don’t want to spend all this money and not have them use it.”

Ms. Alfonzo contacted Freedom Concepts, a Canadian company that builds adaptive bicycles for children with cerebral palsy, muscular dystrophy, spina bifida and other disabilities. James Wall, a representative for the company in the New York area, visited Ms. Alfonzo with two models: large tricycles with seatbelts, foot straps, specially designed handlebars and seats, and sometimes high backs with head support, depending on the disability. The bikes are adjustable and designed to grow with the child for five years.