Speed, radius, and lean
A higher speed or tighter turn requires more motorcycle lean. That leaves less grip for braking and changing your line.
The same turn at a higher speed
If the radius stays the same, increasing speed requires more lean.
A smaller radius at the same speed
At a given speed, a tighter curve requires the motorcycle to lean further.
More lean leaves less reserve
A greater lean angle leaves less ground clearance and less grip for sudden braking or a change of line.
Lane width limits your line
A turn requires a certain lean angle at your chosen speed. If speed increases without more lean, the motorcycle takes a wider line that may no longer fit within your lane.
Sources · 1
- Физические основы классической механики
Криволинейное движение и центростремительное ускорение; PDF: с. 6-7.
Used for: Relationship among speed, radius, and the force required to travel along an arc.
Open source
Even a small increase in speed matters
On the same curve, the required lateral force grows faster than speed itself. Even a small increase in speed can therefore require noticeably more lean.
Entering too fast leaves fewer options
Entering a corner too fast means you will need to lean further, use more of your own lane's width, or brake smoothly while already in the turn.
Enter a blind corner more slowly
When you cannot see how a corner continues, a lower entry speed leaves more time and space if it tightens unexpectedly or an obstacle appears beyond it.
Set your speed before leaning far over
Slow down before entering the corner. That avoids having to brake hard while leaned over and correcting your line at the same time.
Sources · 1
- Физические основы классической механики
Криволинейное движение и центростремительное ускорение; PDF: с. 6-7.
Used for: At the same radius, the required acceleration is proportional to the square of the speed.
Open source
A wider curve needs less lean
At the same speed, a larger turn radius requires less motorcycle lean.
Use a wider line only within your lane
Do not use an oncoming lane, the shoulder, or an unseen part of the road to widen your line. Your radius is limited by the clear, visible part of your own lane.
Do not rush toward the inside of a blind corner
Avoid moving toward the inside of the corner too soon. Holding back preserves your view for longer and leaves more room to change your line if the corner unexpectedly tightens.
Change the radius smoothly
As the exit comes into view, you can gradually straighten your line. If your view becomes more restricted, avoid abrupt steering inputs and first reduce any excess speed.
Sources · 1
- Физические основы классической механики
Криволинейное движение и центростремительное ускорение; PDF: с. 6-7.
Used for: At the same speed, a smaller radius requires greater lateral acceleration.
Open source
The radius can change within a corner
A corner may begin with a broad curve and then tighten. Keep assessing how it continues as you ride through it: a suitable entry speed may be too high for what follows.
When you enter too fast
Reduce speed smoothly and adjust your line without abrupt steering inputs.
Bringing the bike upright frees up grip
As the motorcycle comes upright, lateral demand on the tires decreases. More grip becomes available for acceleration, braking, or a change of line.
Lean, braking, and throttle share the grip budget
A tire is already transmitting lateral force when the motorcycle is leaned over. The same braking or driving force therefore leaves a different margin before grip is lost when traveling straight than it does at a large lean angle.
Sources · 1
- Физические основы классической механики
Криволинейное движение и центростремительное ускорение; PDF: с. 6-7.
Used for: Physical relationship between speed and radius in a steady-state turn.
Open source