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) the flexible end thread is M12.

A few mechanical parts are needed like -bearings (625(ZZ), 608(ZZ)) -some M3 screws -small cylinder magnets (3x3mm)

everything is available on aliexpress

Then magnets are inserted with pliers. and both disks are glued. (cyanoacrylate is working well)

BEWARE: Magnet direction is important on some sensors! Do not forget to put some loctite glue on sensor thread. vibrations are everywhere!!

M12 Plastic thread is a bit weak. So I made a V2 version where it is locked instead of screwed. M3 screws will also be needed to secure that.