Find the biggest gear you can use while standing and without pulling up on
the handlebars. Then compute as follows:
compute the inverse of 4 times the gear ratio.
For example if you can climb in a 42-21 then you get 4 * 42 / 21 = 8, and
1/8 = 0.125 = 12.5%
Why is this a good guess? 4 = 2 * 2,
one 2 is because the crank is about half the radius of the wheel
the other 2 is because you apply force about half the rotation of the
stroke
Then adjust the factor of 4 to suit your style. Perhaps you know a slope of
a steep hill, so try to find the biggest gear you can use.
You could also try to choose a gear that you can balance (speed = zero) with
all your weight on one pedal, and then the slope would be just (radius of
crank)/(radius of wheel)/(gear ratio), or 1/(2*gear ratio). But you would
have to correct for the ratio of your weight (applied to the pedal)/(total
weight including the bike).
Bruce
"Phil, Squid-in-Training" <
[email protected]> wrote in
message news:
[email protected]...
> There's a hill nearby whose gradient or whatever I'd like to guess. How
> should I go about it? I don't have any surveying equipment, and my GPS is
> long gone. I've got a bike and myself.
>
> --
> Phil, Squid-in-Training
>
>
>