SR Suntour has released its long-anticipated TACT electric suspension system, which controls the low-speed compression of a bike's fork and rear shock.
The system has previously been spotted in cross-country competitions underneath riders such as Tom Pidcock and Pauline Ferrand-Prevot.
SR Suntour says the new system is designed for all mountain bike disciplines and expects to implement the technology into its larger forks in the future.
At launch, only a cross-country kit is available in the form of an Axon 34 Werx Boost EQ 29in fork and a new Edge TT rear shock.
The entire TACT system is priced at €4,990, and is currently only available as an aftermarket upgrade.
SR Suntour says the system adds only 198g over a remote-actuated system.
Automatic compression adjustment
Unlike other electronic suspension systems, such as RockShox Flight Attendant and Fox Live Valve, the SR Suntour TACT uses only one sensor to adjust the suspension to the terrain.
A three-axis accelerometer located in the crown of the fork relays information about the terrain to the system and can detect uphill, downhill, flat, weightlessness and vibrations.
The brand says it has designed the system so you don’t need to think about adjusting your suspension on the fly, with TACT always putting you in the best compression settings.
SR Suntour is so confident that the system features no remote lock-out, though rebound and sag settings need to be adjusted manually.
Application adjustment
While the system is automatic, it can be adjusted within the TACT app, which enables riders to set up custom tunes for different courses and trails.
The app allows for eight different adjustment levels, with level 1 providing the most comfort and level 8 maximum efficiency.
One thing we didn’t spot when watching Pidcock and Ferrand-Prevot race this season was the external battery pack required to operate the system.
The battery pack is mounted on the down tube next to a bottle cage. SR Suntour says this helps keep the weight central, reducing any impact on the bike's agility.
The brand says the battery has been hidden inside the Pinarello Dogma XC frame for the Ineos Grenadiers riders, with similar integrations expected in the future.
SR Suntour says it has chosen a wired design because it's the fastest way for the components to communicate with each other, allowing for a four-millisecond reaction time to trail features. The brand has yet to mention how the system affects pedal bob.
The Axon 34 Werx Boost EQ fork features a hollow carbon fibre crown with magnesium lowers, and is available with 100mm, 110mm or 120mm of travel for ever more demanding XC courses.
A new Edge TT rear shock sees an external air pipe design, which SR Suntour says makes for easy air-volume tuning on the bike.
Mounting the system requires attaching a long battery mount to the bottle cage on the down tube, which may cause compatibility issues on some small frame sizes.
SR Suntour is yet to confirm if any bikes will hit the market with the TACT system integrated.
