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11-14-25 | 08:11 PM

#59

genejockey

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The formula for a circle is (X - H)^2 + (Y - K)^2 = R^2, where R is the radius, H,K are the coordinates of the center of the circle - the BB center in our example, and X,Y are the coordinates of any point on the circle - the position of the pedal spindle. So, if we set H and K to 0, that puts the BB center at the origin. Here's what you get with an R of 170:

And here's what you get if you make Y into (Y - 5), to reflect a 5mm pedal stack, so we're following the path of the pedal top, rather than the spindle

Same circle, offset vertically by 5mm.

Edit: In case you don't believe it:

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Last edited by genejockey; 11-14-25 at 08:18 PM.

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