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Old 01-28-2013, 08:01 PM   #17 (permalink)
mort
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Quote:
Originally Posted by sendler View Post
So the difference between 1st and 6th in the acceleration you feel is entirely due to wind resistance?
Hi sendler,
No, it is the road speed that matters the most. Power makes the thing go and the amount of power required at any speed depends on the speed.
If you use the ecomodder calculator here (note: the aero and rolling resistance forces are shown in Newtons) and think motorcycle... you get 30 hp needed to keep going 100 mph.

But the amount of power it takes to accelerate also depends on your speed. The acceleration is just like any other force being applied to the bike. Let's say you want to accelerate at 1 g, and you are going 50 mph. Again according to the ecomodder calculator, that would require 80 hp.
But how much power does it take to accelerate at 1 g at 100 mph. Your speed has doubled so the power has doubled: 160 hp.

So comparing the acceleration at 10 mph and 60 mph means comparing one condition with another that will require 6 times as much power - put another way: The same amount of power available at 10 mph and 60 mph will deliver 1/6th the acceleration.


Also I think the ecomodder calculator is wrong.
-mort
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