2018 Tour de France champion Geraint Thomas urged people to oppose plans to demolish his home bike path.
The Maindy outdoor track is expected to make way for an extension of the school and will be replaced by a new velodrome at Cardiff Sports Village.
The track is home to the Maindy Flyers, where Thomas started his career.
“Without Maindy Stadium I would never have fallen in love with cycling, as well as many children,” he said.
His fellow Welsh cyclists Elinor Barker, Owain Doull and Luke Rowe also started on the track.
Thomas, 35, supported a petition against the project which is subject to planning approval.
Cardiff adviser Russell Goodway told the local democracy information service hope that the construction of the new track will begin “early 2022”.
A Cardiff Council spokesperson said: “Plans for the new velodrome in the bay are supported by key cycling organizations including British Cycling, Welsh Cycling, Welsh Triathlon, Maindy Flyers, Cardiff Ajax and many other cycling clubs of the region.
“They helped us define the specifications of the velodrome so that it will work for the majority of people who will want to use it, from beginners to professional racers.
“We look forward to sharing these plans with Geraint upon his return from Tokyo. His success has thrilled a new generation of Welsh cyclists and we believe the new velodrome will give them the arena where they can learn to hone their skills by creating new ones. memories and new medalists. ”
A spokesperson for Welsh Cycling said: “Welsh Cycling has been involved with the Cardiff Council in the discussions on the relocation of the velodrome from Maindy to the Sports Village and is excited about the opportunities this will bring for cycling.
“In addition to Welsh Cycling’s involvement throughout the process, British Cycling also provided technical input. In addition, we were assured of continuity of use between Maindy and the new installation.
“The development will include a specially designed velodrome with modern facilities, including a club house and a spectator stand, as well as a 1 km closed road circuit and a full-size bicycle shop.
“We believe this will be a great facility to replace Maindy for existing users and provides a great opportunity to attract new riders to this exciting new facility.”
