ran 95 cub deuce, before and after , fitting mammoth spoke rim , mammoth spoke rim 15 kg heavier , dyno sheet , shows any thing hearier to drive from crank back will sook up rwhp reading s 

This was orig duece wheel compared to heavy spoke wheel hilly , people wonder why there bike doesn't show as high as similar , 

most bike dynos are enercia type dynos ie the measure the time it takes to accelerate the roller & as you have added extra weight in the driveline it takes extra horsepower to accelerate the extra weight you have added , if tested on a brake dyno where the roller is held at a constant  load the result would be different