Bouncing at high cadence is not balance or the bike, it's your muscles not being able to cope with expanding and contracting at that rate, and it is those muscles that inadvertently cause you to wobble and bounce.
The more you spin, the less you bounce when you spin.
Take spin classes.
Bouncing at high cadence is not balance or the bike, it's your muscles not being able to cope with expanding and contracting at that rate, and it is those muscles that inadvertently cause you to wobble and bounce.
The more you spin, the less you bounce when you spin.