In this article we explain what this point is, why it is crucial for handling and efficiency, and what to look out for when buying an MTB.
What is the kinematic point?
The kinematic point , often also referred to as the instant center of rotation (ICR) , is a theoretical point in the rear suspension of a full-suspension mountain bike. It describes the position around which the rear wheel moves when the suspension compresses. In other words, when the rear wheel is moved upwards or backwards under load or when riding over obstacles, it "rotates" around this point – even if it is not physically visible.
The position of this point influences how the bike reacts to pedal forces , braking forces , and uneven surfaces .
Why is the kinematic point important?
The position of the kinematic point affects several aspects of driving behavior:
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Pedal efficiency and anti-squat
Depending on where the kinematic point is located, the suspension is subjected to more or less stress when pedaling. If the point is optimally positioned, the mountain bike hardly squats at all while pedaling – this effect is known as anti-squat . This ensures efficient progress, especially uphill.
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Responsiveness to obstacles
A well-positioned kinematic point allows the rear wheel to cleanly absorb bumps without the rider feeling every imperfection in the road. This increases control, comfort, and traction.
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Braking stability
The suspension reacts not only to pedal forces but also to braking forces. An optimal kinematic point ensures that the suspension does not compress uncontrollably under braking, but rather that the rear wheel remains stable – minimizing the notorious brake-through effect .
How is the kinematic point determined?
Engineers determine the kinematic point through geometric analysis of the rear suspension kinematics . This involves connecting the pivot points of the linkage bearings, swingarm, and shock absorber to find the theoretical pivot point. Modern CAD programs allow simulation under real riding conditions, enabling designers to optimally balance anti-squat, responsiveness, and braking stability.
Kinematic point and chassis design
The placement of the kinematic point depends heavily on the chosen rear suspension system :
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Horst Link (four-joint system)
The kinematic point is often positioned to create a balanced compromise between anti-squat and suspension travel. This makes the system suitable for versatile trail and enduro bikes.
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Single Pivot / Virtual Pivot Point (VPP)
Single-pivot bikes have a fixed pivot point, which makes the kinematics simpler but less adaptable. VPP systems work with two pivot points, whose combined movement creates a more dynamic kinematic point.
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Linkage Designs
Designers use complex deflections to selectively shift the kinematic point for different suspension travel – for maximum pedaling efficiency and minimal braking interruption.
What does that mean for the driver?
For mountain bikers, kinematic point optimization means:
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Improved efficiency on the mountain – the bike doesn't "swallow" the pedal power.
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Greater comfort off-road – bumps are absorbed better.
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Control during braking – the rear wheel remains stable, even on tough downhill sections.
Anyone buying a mountain bike should therefore not only look at the suspension travel length or the type of damper, but also pay attention to the rear suspension kinematics .
Conclusion
The kinematic point of the rear suspension is invisible, but crucial for the riding feel of a full-suspension mountain bike. It influences pedaling efficiency, braking stability, and suspension response – in short: how well a bike can "read" the trail.
Understanding rear suspension kinematics allows you not only to make the right adjustments for the shock and suspension, but also to choose a mountain bike that perfectly suits your riding style.
