Universal speedometer speed sensor

This part is a speed converter from a rotating cable connected to a motorbike frontwheel, to a universal speedometer.

Speedometer needs a magnet rotating in front of a hall sensor.

Putting this sensor on the wheel isn't nice, and sometimes impossible or dangerous (using brake disk to put magnets on isn't a good idea.

So I came to the idea to use the existing mechanical cable (only on old bikes? mine is a 94' Suzuki GS500).

The flexible cable has to be a square profile (2.5mm)
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