Trail: Steering Geometry
How exactly a bicycle remains upright is open to debate, with many a graduate student putting in late nights trying to figure it out on paper. Steering geometry and the basics of what makes a bike handle predictably is better understood, or at least falls into some generally agreed upon parameters. Bikes tend to look like bikes afterall, with the geometry differences between similar purpose bikes being fairly subtle. That said, small geometry changes can have large effects on a bike’s handling, especially when it comes to swapping forks. It’s best to stick to the numbers your bike was designed for, or at least go into things knowing enough to be dangerous.