The Isle of Man TT has announced significant changes to the Sidecar category for the 2027 event, following a difficult 2026 TT that saw the entire class suspended from the competition programme after incidents during practice and qualifying.
The changes come after several months of analysis and discussions between the organisers. However, the new regulations will apply specifically to the 2027 event, with further adjustments to the sidecar format expected for 2028 and 2029 as the organisers assess how the category develops.
One of the biggest changes will be the removal of the 600cc four-cylinder engines that have powered modern TT sidecars. From 2027, teams will instead be able to use modern middleweight motorcycle engines, including units from the Aprilia RS660, Kawasaki Ninja 650 and Yamaha R7, among others.
The new regulations will also introduce a Balance of Performance approach. According to the organisers, this is intended to reduce the advantage gained through significant investment in engine development and create greater parity between competitors. How effectively the system achieves that balance, however, will become clearer once the motorcycles return to the Mountain Course.
Changes will also be made to the chassis regulations. Existing sidecar chassis designs will remain eligible for competition in 2027, helping teams avoid the cost of completely new machines while the category transitions to the new regulations. At the same time, new requirements covering areas such as chassis construction and modifications will be introduced.
The race format will also change, with both of the two Sidecar races at the 2027 TT scheduled to run over two laps of the course. Alongside the technical changes, the organisers will introduce stricter eligibility requirements for competitors. Riders and passengers will need to demonstrate recent competitive activity and medical fitness, with the specific requirements to be detailed in the revised regulations.
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The organisers say the staged approach to changing the Sidecar category is intended to provide a sustainable way forward, with the rules set to be reviewed and further developed after the 2027 event.



















