Advanced Motorcycle Stabilization Assist System (AMSAS)

Controlling drive and steering forces for rider-machine unity

Yamaha has set a target to reduce the number of fatal motorcycle accidents to zero by 2050, through Technology, Skills, and Connectivity. The announcement of its Jin-Ki Kanno x Jin-Ki Anzen Safety Vision is another step towards creating a world without motorcycle accidents. 

Pillars of the approach:

1) Technology that assists with rider recognition, judgment, operation, and damage mitigation 

2) Encourage the improvement of users’ riding skills, 

3) Connectivity, where the Cloud provides feedback for safety initiatives


Accidents involving motorcycles have been attributed primarily to recognition errors (10%), decision errors (17%), and rider operation errors (5%). Data also indicates that approximately 70% of motorcycle accidents occur within two seconds of the trigger leading to the accident. Based on these analyses of accident causes, Yamaha Motor’s development of rider aids is underway according to four vectors: assisted danger prediction, damage prevention and assisted defensive riding, assisted evasive riding maneuvers, and damage mitigation.

Unveiled last year, AMSAS stabilises a vehicle’s attitude at low speeds by controlling drive forces and steering forces. “Its most distinctive feature is its approach to use, which is highly applicable to existing vehicles since it does not require any modifications to the frame,” says Project Leader Akitoshi Suzuki. The prototype system under development uses a production YZF-R25 for its platform, equipped with a 6-axis Inertial Measurement Unit (IMU) along with drive and steering actuators.

 AMSAS is a rider aid focusing on the instability motorcycles experience when moving from a standing start or riding at low speeds. The system works to enhance the stability of the vehicle during these moments. “When starting or stopping, the drive actuator fitted to the front wheel aids with stability, and from there up to about 5 km/h, the steering actuator attached to the handlebars takes over,” explains Suzuki. Through the coordination of the two, the mid-development AMSAS prototype vehicle can move at walking speeds without falling over, regardless of the skill level of the rider aboard.


Yamaha Motor once made headlines when it unveiled the MOTOBOT–an autonomous motorcycle-riding humanoid robot–and MOTOROiD, a proof-of-concept experimental motorcycle equipped with AI and self-balancing technology. “The R&D for AMSAS began with the idea of bringing the technologies and know-how acquired through developing these two models to customers worldwide,” says Suzuki.


Jun Sakamoto, who handles safety strategy at Yamaha, explains the value AMSAS aims to offer: “It’s to create conditions where the rider can focus more on operating their bike. By providing an assist when the bike is more unstable and requires skill to operate, we want to deliver fun rooted in peace of mind to a wide range of riders.”

Yamaha has set a target of reducing the number of fatal motorcycle accidents to zero by 2050 and is ramping up efforts through Technology, Skills, and Connectivity. AMSAS is one technology with the potential to become a pivotal rider aid if used with other technologies, like the radar-linked Unified Brake System–the first of its kind in the world–already deployed on the TRACER 9 GT+.

 “With the base technologies in place now, we’re halfway to our goal of bringing AMSAS’ value to customers,” asserts Suzuki. He and the team have high aspirations for the technology: “From here on, we’ll be working on downscaling the sizes of the various components and so on, as we want to develop it into a platform not just for motorcycles, but one also adaptable to a wide range of other personal mobility applications, like bicycles.”