Born in 1945 in the province of Udine, although he received his motorcycle training in the Monza area, athletic (he made his sports debut as a cyclist), exuberant and free and easy-going, Bonera often fell short of important goals not owing to his lack of talent as a rider, but because of his impetuous nature. MV signed him in 1974 because it felt the need to grow a new talent that would fill the void left by Agostini (who switched over to Yamaha).

He claimed two important races in the 500 class, ending the season in second place in both the World and the Italian championships behind riders of the calibre of Read and Agostini, respectively. In the first race of 1975, he took too great a risk and hit a bale with his knee. The injury put him out of the running for a good part of the season. Then at Mugello, while he was in the lead 15 seconds ahead of Agostini, he took a frightening fall that ended his race and his brief relationship with MV. A short while afterwards Bonera once and for all quit racing to devote himself to business activities in the world of motorcycling.