Exhaust gas control means for motorcycle and the like
AssigneeYamaha Hatsudoki Kabushiki Kaisha
InventorShinji Shiraishi
Life of this patent
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Abstract
A number of embodiments of motorcycle exhaust systems including control valves for controlling the effective area of the exhaust pipes and for improving performance by preventing reflections from one exhaust pipe back into the cylinder served by another exhaust pipe. The valve means lies under the engine crankcase and the crankcase is formed with a recess for clearing the valve means and permitting air flow across it for cooling purposes. Various valving arrangements are disclosed as is a skid plate arrangement for protecting the valve means.
Claims30
In an internal combustion engine comprised of a crankcase defined of a crankcase housing, a plurality of exhaust ports formed in a side of said engine, a plurality of exhaust pipes extending from said exhaust ports downwardly and passing beneath said crankcase housing, valve means in said exhaust pipes for controlling the flow therethrough, said valve means lying beneath said crankcase housing, and a recess formed in said crankcase housing through which at least a portion of said valve means in said exhaust pipes pass.
A valve member for controlling the effective area of a plurality of exhaust pipes comprising a valve housing defining at least an upper exhaust gas passage and a lower exhaust gas passage, an upper valve shaft rotatably journaled in said valve body and extending through said upper exhaust gas passage, a lower valve shaft journaled in said valve body and extending through said lower exhaust gas passage, valve elements affixed to said valve shafts for controlling the effective area of said exhaust gas passages, an operator affixed to an exposed end of said lowermost valve shaft, and motion transmitting means for transmitting motion from said lowermost valve shaft to said uppermost valve shaft.
In a vehicle powered by an internal combustion engine comprised of a crankcase defined by a crankcase housing, a plurality of exhaust ports formed at one side of said engine, a plurality of exhaust pipes extending from said exhaust ports downwardly and passing beneath said crankcase housing, valve means in said exhaust pipes for controlling the flow therethrough, said valve means lying beneath said crankcase housing, and a skid plate affixed to said vehicle and lying beneath said valve plate valve means for protecting said valve means.
Dependencies are inferred from the claim text.