Are the suspensions of any scooter adjustable to deliver a smoother ride

Scooter suspension is not adjustable/modifiable.

Most scooters wheels are fastened directly to the scooter chassis, meaning that the rider is going to feel all aspects of the the riding surface.

Some scooters have a spring-loaded suspension similar to what is found on cars. The spring suspension provides an overall better ride than one without. This is because the wheels are fastened to a sub-chassis which is connected to the main chassis with springs. This will deliver a more "springy" ride over one that doesn't have this feature. The exact amount of the difference is dependent on the weight of the rider and the actual road surface.  

Neither kind of suspension design is adjustable for ride.  

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