Bike Forums - How much of a difference do hills make for average speed?

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Quote:

Originally Posted by bikerjp (Post 12710853)

It's not necessarily twice the slowest speed (look at the examples on the previous page), but you are right that hills will always lower the average speed compared to flat ground. Why some people fail to understand this is beyond me.

It makes me wonder if they do much climbing, then. My example is true when there's an equal amount of climbing/descending, like if you do an out and back.

When you climb these long mountain roads as slowly as I do, you have alot of time to consider such things... :)

Quote:

Originally Posted by DScott (Post 12710884)

Agreed. But as for the twice the slowest speed part I think that is just in the math as the downhill speed approaches infinity or even just a ridiculously high speed. Take a look at this example from a couple pages back.

12.5 MPH up a 3% hill
31.6 MPH down a 3% hill
17.9 MPH average

You will approach 25 mph average, mathematically, as the downhill speed gets large.

2 / ((1 / 12.5) + (1 / 1000)) = 24.691358

So, the real question then is when I have a 15 mph average speed with significant climbing, does that mean my average over flat ground would have been close to 30 mph? I think I'll choose to believe that as it makes me awesome. :)