Learn the flat corner: brake early, load the front wheel, lean the bike and weight the outside pedal. 5 steps with milestones, mistakes and safety notes.
The honest answer first: a flat corner is a corner without banking, so without a berm. You ride it by slowing down beforehand, loading the front wheel, leaning the bike into the corner and weighting the outside pedal. The outside pedal increases the contact pressure of the tyres [1].
The term "flat corner" belongs to the riding-technique scene (practice), the technique behind it is documented. BASPO, the Swiss Federal Office of Sport, distinguishes slow corners that you steer from fast, flowing ones in which you lean the bike in, and says clearly: relaxed, flowing and safe cornering is more important than clinging to one technique [1].
Why does it matter? In 534 analysed crashes, about every fourth one ended sideways: 12.2 percent sideways ejection, 10.9 percent sideways sliding [2]. And when a wheel slips, the probability of head impact rises clearly (odds ratio 3.1) [3]. The flat corner is a skill where mistakes quickly punish you.
How hard is it? You learn the technique on the lawn in an hour. On changing ground you need months of experience (experience-based), because every surface grips differently.
In a flat corner grip is not a property of the ground, but something you give the tyre.
Accelerate or brake to the right speed before the corner begins. Eyes: as far into the corner as possible, that is where you look for the line [1]. The bike goes where your eyes look. Look to the apex and shortly after to the end [5].
Milestone: you brake to target speed at a cone, five times in a row.
Rise briefly and let yourself fall into the corner. You go low and press the bike into the ground, which increases grip [1]. Your centre of mass stays central and low.
Milestone: on the video you see that your hips are lower than when rolling in.
The bike lies in the corner and you lean bike and body in. The inside arm is slightly straight, the outside elbow bent [1]. The outside hand pushes the bars and loads the front tyre [5].
Milestone: the front wheel holds the line and you hear no pushing or squealing.
The cranks are level or the outside pedal goes down and you load it. This increases the contact pressure of the tyres [1]. Hips, upper body and knees point to the corner exit.
Milestone: you ride the circle on the lawn with a constant line and the rear wheel does not slide.
Avoid braking in the corner where possible [1]. On exit you release the brake and use the momentum as soon as steering angle and trail allow [5]. Eyes already on the next target.
Milestone: five corners in a row without putting a foot down.
The risk of the flat corner is the moment the front wheel slips. Falls forward had almost five times the odds of head impact in an analysis of 300 falls (odds ratio 4.9) [3]. In mountain biking the head and upper extremity are the most common injury sites [6]. In a meta-analysis across cyclists, a helmet cut serious head injuries by about 60 percent [7], a figure for cycling in general.
Wet ground, leaves and loose gravel take away grip (practice). Increase lean first, then speed, never both at once. This guide explains and motivates, it does not replace supervised training.
Your line depends on the surface, not on the rule "enter wide, pull inside". Axel Head stresses that this often-read rule is not generally valid: besides the radius, the ground decides above all [5]. Walk the corner once on foot, look for the grippiest line and ride that.
Brake to target speed before the corner, eyes into the corner, rise and let yourself fall in, lean the bike, weight the outside pedal, avoid braking in the corner [1].
Common reasons: too little load on the front wheel, braking in the corner or too little grip from the ground. The front tyre steers and needs pressure [5]. Wheel slippage was a clear risk factor for head impact in a video analysis [3].
The outside one. It increases the contact pressure of the tyres. Alternatively the cranks are level [1].
Fast enough that you stay fluid and relaxed. BASPO considers looseness and flow more important than clinging to a technique [1]. There is no fixed km/h figure, it depends on the ground.
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