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0 pointslelanthran9mo ago0 comments

>There's a decent amount of lag (delay between application of a force by the user and force at the throttle) and non-linearity in a 2-foot cable caused by elasticity of the cable and the cable guide and friction between the cable and the guide.

What sort of motorcycle was this? The ones I had had metal cables; there is no elasticity (if it stretches, it ain't shrinking - you'll adjust it to take up the slack).

Friction between cable and guide also doesn't cause lag.

(Still want to know how it is more safe)

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2 comments · 1 top-level

hollerith9mo ago· 1 in thread

By "elasticity" I mean any change in length in response to a tensile or compressive force. A thin steel cable is quite elastic in response to the forces on it in this application (i.e., a lot more force than you can apply to the cable with your bare hands).

Friction causes the force at the brake to be non-linear (and importantly unpredictably so) in the force applied by the user.

If you had said that this elasticity and this non-linearity (and unpredictability) are small enough to be irrelevant in a properly designed motorcycle, I would have no way to contradict you: I don't know enough. But GGGP's comment[1] is evidence that they are large enough to be relevant.

[1] "I have throttle-by-wire on my motorcycle and I love it. Very precise and safe."

lelanthranOP9mo ago

> But GGGP's comment[1] is evidence that they are large enough to be relevant.

GGGP is talking about fractions of a millimeter in elasticity in the steel cable.

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