BSFC maps


New Member
Feb 12, 2009
Would anyone know of any BSFC maps for any small single cylinder engines.
Brake Specific Fuel Consumption (BSFC) is a measure of how efficient an engine is, it is generally reported as g/kwh but this can be directly converted to %age efficiency of the engine (410 g/kwh is around 19% efficient, 340 g/kwh is around 24% efficient).
When in use an engine's efficiency is affected primarily by two variables, the speed of the engine (RPM) and the throttle location (which gives the vacuum/air pressure in the inlet manifold). A BSFC map displays a contour map of the efficiency, with RPM on on the X axis and throttle location on the Y axis.
Honda's and Robin's product information sheets both show BSFC charts for their engines, but these only show BSFC for RPM (presumably at a set throttle location?)
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