Davide Nicola made the deal in April, when Crotone looked certain to go down.
But they won six of their final nine matches of the season to avoid the drop by two points, after having won just three games from their previous 29.
The 44-year-old arrived in his home town of Vigone near Turin on Sunday - nine days after leaving Crotone.
"Am I tired? I still do not feel any particular pain," he said.
"It's been a beautiful journey, a fairytale. From tomorrow maybe I will feel a bit tired, but what matters most to me is that my goal has been achieved."
Three years ago, Nicola's 14-year-old son Alessandro was killed after being knocked off his bike by a bus in Vigone.
"I kept the promise and, with the help of many people, we have also attracted the attention of many people to the question of safety on the roads," he added.
"Here in Turin I was greeted with great enthusiasm, I am very excited."
Nicola made the deal with his players after a 2-1 win at Chievo - Crotone's first victory away from home in Serie A.
Crotone took just 14 points from their first 29 games but won six of their last nine matches to finish on 34 points, two points above the relegation zone.
Even with their remarkable late run, the side began the final day of the season in the bottom three, but a 3-1 win over Lazio and Empoli's defeat by Palermo saw them survive in their maiden top-flight campaign.
A Serie A manager has completed a 1,300km bike ride up the length of Italy, after telling his players he would do so if they avoided relegation.