Isle of Man TT announces major Sidecar overhaul for 2027

The Isle of Man TT has announced a raft of major changes to the Sidecar class from 2027, following a review into the viability and sustainability of the category.

The Sidecar class was suspended following two major incidents during qualifying week for the 2026 TT, including an airborne shunt for the Crowe brothers.

In the aftermath of this, the TT carried out a detailed review of the class, opening discussions with all relevant parties to understand the viability and sustainability of the category longer-term.

The review found there was an overwhelming desire for the TT to continue hosting Sidecar races, but it was also agreed that the current regulations had to be changed.

For 2027, a host of changes to the Sidecar rules will be implemented as part of a three-year commitment to the class.

New engine format for Sidecar class

The biggest change to the rules is to the engine formula, with the TT now moving away from the long-standing 600cc four-cylinder framework.

Instead, permitted engines will be based on production-spec middleweight machinery based on Sportbike rules.

This includes the likes of the Yamaha R7, Aprilia RS660 and Kawasaki Ninja 650.

The idea behind this change is to control speeds, but also provide a more sustainable development path for competitors.

The Sidecar class will use Mectronik ECUs from 2027, while a Balance of Performance system will come into force in order to keep the category competitive.

Chassis and bodywork changes incoming

The TT also announced that current Sidecar chassis can continue to be used, which will keep costs down for competitors.

However, clearer limits on bodywork designs will come into force in a bid to cut down on aerodynamic development.

There will also be changes to weight, fluid containment, as well as machine safety and technical compliance. These rules are yet to be finalised, however.

Sidecar races will be shorter at TT 2027

The Sidecar class will continue to compete at the TT for at least the next three years, though these races will be shorter than previously next season.

From 2027, Sidecar races will be run over two laps instead of three.

The qualifying schedule will remain the same, while the shorter races are seen as a “more conservative” race format at least for 2027.

Further changes to the rules for 2028 and 2029 will be reviewed based on competitor feedback next year.

Clerk of the Course, Gary Thompson, said of the new rules: “The move to the Sportbike engine framework and controlled electronics is a significant change, but it gives us a much greater ability to manage the performance of the class.

“It also recognises where the motorcycle industry is heading. The 600cc four-cylinder platform has served Sidecar racing extremely well, but we need a formula based around modern production engines that can remain relevant and sustainable into the future.

“There is an important sporting benefit too. The combination of controlled electronics and Balance of Performance should allow us to achieve much closer performance equivalence between the different engine configurations and reduce the advantage available simply through spending heavily on engine development.

“The aim is a more controlled and competitive formula, with greater emphasis on preparation, chassis set-up and, ultimately, the performance of the driver and passenger.

“Detailed engine eligibility, permitted modifications, electronics, chassis, bodywork, weight and compliance requirements will now be finalised ahead of publication of the 2027 TT Sidecar Technical Regulations.

“Further details on the 2027 sporting regulations, entry requirements and schedule will also be confirmed in due course.”