According to the Manchester Evening News, engineers were forced to take down the 10m metal spikes due to safety reasons and even had to close off one lane of Aston New Road to gain access to the 18m-tall structure to carry out the work.
News of the work will come as a fresh blow to Heatherwick who, along with subcontractors Packman Lucas, Westbury Structures, and Flint and Neil Partnership, is about to be hit with a £2 million High Court writ lodged by the council over structural issues. A hearing is set for October.
Trouble started for the £1.4 million sculpture right from the start, after it was commissioned to celebrate the 2002 Commonwealth Games in Manchester.
It overran its completion date of July 2003 and was only officially unveiled in January 2005. A week earlier the first of the 180 metal spikes fell off the sculpture.
At the time of writing Heatherwick was unavailable for comment.