How to install a gyro on your BMX bike (video in German)
A rear brake opens up a lot of tricks, and being able to slow down quickly is simply safer. The cable gets in the way though, which is what a gyro solves: it lets you spin the bars as often as you like without the cable winding up.
Fitting one looks harder than it is. The video shows the whole job step by step; the rotor set used in it is the Vocal.
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Please note: this video is in German.