Whatever Happened To...MV Agusta's Boxer Four?

Words: Aaron Frank

Photo: Rich Chenet

When MV Agusta won 17 straight 500cc World Championships from 1958-’74, it set a record that will never be broken. But by ’76 the Italian company was in dire straits, its signature four-stroke fours unable to win against lighter, faster two-strokes. When Giacomo Agostini, winner of seven of MV’s 500cc titles, abandoned the Italian marque for Yamaha—where he ended MV’s winning streak in ’75—it was the last straw.

[MV Agusta’s fat-four isn’t a true boxer— technically, it’s a 180-degree, singlecrankpin fat-four. It mounts longitudinally in a trellis spaceframe to allow chain drive.

MV Agusta scrambled for a silver-bullet solution to lure Ago back. Chief Engineer Guiseppe Bocchi—formerly of Lamborghini and Ferrari—developed this four-stroke, horizontally opposed four-cylinder engine to power its next-generation GP bike. Featuring the same bore and stroke as MV’s inline-four but with more radical valve geometry, liquid-cooling and experimental fuel-injection, the new motor borrowed heavily from the flat-12 Bocchi previously developed for the Techno PA Formula 1 effort.

The flat-four design showed great promise on the test bench, but development halted after MV Agusta withdrew from Grand Prix competition in ’76. Team Obsolete’s Rob Iannucci has owned the two surviving flat-four prototypes since the mid-’80s, and is currently restoring both to running condition. It's doubtful the flat-four could ever match an equal-displacement two-stroke, but it certainly is a fascinating piece of history. Fortunately it wasn't lost to time. We hope to hear it running soon!