GRI is a British historical brand of motorcycles.
The company name was: Macrae & amp; Dick Motorcycles, Inverness.
The brand name was derived from the engine's initials: G.R. Inshaw. It had a motor built with only one normal valve. The inlet valve was replaced by a rotating disc. The engine was available as a 348 and 496cc version, but rotating discs had failed before and the public had little faith in it. Perhaps that is why the GRI motorcycles were built only in 1921 and 1922.
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