| An O ring chain alone will lose 10% of crank power, then the the condition of the sprockets and not to mention the lubrication and wheel weight.
As a guide, power at the back wheel is around 20% less than the crank.
So the R6 with 120bhp will lose 24bhp through the drive train and a more realistic figure of 96bhp appears.
Judge for yourselves. | 
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