As cycling grows in popularity as a sustainable transport mode in Europe, cyclist safety has become a priority. Advanced Cyclist Assistance Systems (ACAS), inspired by ADAS, offer potential safety improvements but remain underexplored. This study examines ACAS acceptance among 5,991 cyclists from 19 European countries, focusing on public perceptions and adoption drivers. Acceptance varied across countries, with higher rates in areas with strong cycling infrastructure; safety and reliability were universally valued, though gender differences emerged (women prioritised safety and visibility; men favoured usability and added features). The findings highlight the importance of infrastructure, reliable technology and awareness efforts to promote adoption.