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Comment by Gracana | Hacker News Reader

> As in, you only counter steer a motorcycle above ~10mph

I don’t believe that this is true. Can you explain the physics?

Go play with the animation in the article after the text

> In this next demonstration, the wheel is spinning around the red axis, and you can also apply a torque that rotates the wheel around the green axis:

At highway speeds on a motorcycle, this effect is very strong.

But at low speeds in a parking lot, any gyroscopic effect of the slow wheels is nothing compared to a 250lb+ motorcycle.

Bicycles work the same way when you're moving very slow.

Ride a motorcycle for 5 minutes and you'll believe.

EDIT: To answer your question more directly, you are steering in one direction to initiate a lean in the opposite direction. E.g. if you are attempting to turn right, you first steer left which generates force in a left-sided contact patch in the front tire, which causes the bike to lean right. The bike then assumes a stable right lean angle (you have to do some work with your body, but the bike naturally wants to do this), and the front wheel comes back into alignment, and you are now turning right.

A good explanation: https://www.youtube.com/watch?v=PgUOOwnZcDU Some more detail: https://en.wikipedia.org/wiki/Countersteering

EDIT 2: I misread your point. You are correct, counter-steering still applies at low speeds but the "feeling" is masked by lack of momentum.

I have one. I still countersteer to turn in parking lots.

In parking lots. It's a different steering regime at lower vs higher speeds.

Yeah, but you quickly counteract with direct steering after you initiate the turn, so the overriding sensation is one of direct steering at low speeds, even through the physics is the same. This is what I think most people are referring to when they talk about high speed / low speed steering.

The "counter steer isn't real" debate about to start again!

The debate is whether countersteering is something you have to consciously do by turning the steering column ("yaw"), or whether it's an automatic effect of pushing/leaning down on the side you want to turn toward ("roll").

"countersteering isn't real" because "steering isn't real", cycles at speed turn by leaning/rolling, not steering/yawing.

If you need to quickly swerve out of the way of an obstacle you push hard on the handle and you will immediately initiate a turn (you could just as easily say that your are initiating a lean). It's also well understood that handle bar input allows you to increase / adjust the lean mid-corner. I ride and never knew there was a debate about this.

Countersteering and roll are not mutually exclusive. The countersteer generally happens when steering whether you think about it or not. If you know about countersteering, you can practice it to make emergency turns.

For roll, Leaning in the direction of the bike is actually a bad habit (but it'll be fine on most road turns)

It turns out you want to lean the bike, and lean/shift your body in the opposite direction. This keeps center of mass above the wheels.

For example, the pro motorcycle racers with their knee an inch off the ground,they're leaning their body weight away from the turn, away from the ground. Meanwhile their bikes are leaning crazy hard.

That style of leaning is important for fast descents, or switchbacks, particularly switchbacks. Eg: "MOUNTAIN BIKE TIPS: CORNERING WITH CONFIDENCE" (start at 1:45) https://youtu.be/GFKPtEzE4xw

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