This is not from Chennai but from Thane, Maharashtra, but something that can be tried here too.
A large apartment complex had many abandoned bicycles and tricycles cluttering up the nooks and corners and passages. The society collected all of them and donated them to an NGO who would refurbish them and give to deserving children. The owners were given sufficient time to claim the cycles if they want.
Are there such NGOs in Chennai that can take responsibility for refurbishing and identifying genuine candidates?
This is one of the ideas I picked up from my recent travel.
Captured with Xiaomi Redmi Note 4