Pursuit Geometry/Fork Rake Explained

I've been getting quite a few questions on Pursuit Geometry. This is a perfect explaination found on the inter-web. This snippet explains fork rake and HT Angle.

"Head tube angle is directly related to the fork rake (the perpendicular distance from head tube center to the center of the front wheel axle). Combined, these two dimensions have great bearing on how a bike handles in turns as well as in a straight line. To understand the relationship, you need to be aware that for every head tube angle and wheel dimension there is only one rake dimension that will provide neutral steering. Neutral steering means that the fork will not rise or fall as it is turned. As the head tube angle increases (gets steeper) the rake is shorter , as the angle decreases (gets shallower), the rake gets longer. The steeper head tube and shorter rake provide quick steering and a stiff front end that is desirable for racing. Another effect is that it pulls the wheel under the rider improving stability in a sprint. The bike has less of a tendency to sway or whip side to side and provides for efficiency of power. If however, the angle is too steep and the rake too short, the bike can become difficult to control and will result in a very harsh ride and excessive wear on the headset. A shallow head tube angle decreases steering sensitivity since the wheel is more out in front of the rider. This gives a springy ride but less responsive or sluggish steering requiring more aggressive input even at modest speeds."

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