I bought a Varstrom conversion kit (gear-less front hub motor, VD18MT display) and I've exactly the same controller (YCSY126-043-48TC6) as mentioned in the first post. Tested it and have similar problem with the pedal assist. In my case it's not as sharp as described in the first post but when I rotate the pedal assist sensor the motor reaction is very non-linear. It can be best observed at highest assist level.
When I very slowly rotate the magnet ring the motor either doesn't turn at all or immediately reaches 10 km/h (the bike is placed with wheels up so the motor works without load). It's not easy to maintain this speed rotating the magnet ring by hand. Then small rotation increase causes a rapid increase in the displayed speed and you don't need to rotate much faster to reach the maximum speed (50 km/h). A small rotation decrease and the motor stops driving the wheel.
Fortunately, the included left PA sensor doesn't fit my bike so I also purchased a bigger right side sensor (exactly this one https://allegro.pl/oferta/czujnik-e...wojne-czujniki-hallowe-12-magnety-13905770397).
And bang! With this sensor everything seems to work much better. At the same highest assist level you can easily maintain 4 km/h rotating the ring slowly by hand and then easily increase rotation to display any speed you want. It seems that this sensor is much more linear than the one included in the kit.
I still didn't finished this conversion because the bolts on the motor on the disc brake side stick out too much. But I'm now more optimistic about this YCSY126 controller.
I would like to point out that I changed two things in the controller configuration: the number of assist levels from default 5 to 9 and the speed limit from default 99 km/h to 50 km/h (maybe it also matters).
When I very slowly rotate the magnet ring the motor either doesn't turn at all or immediately reaches 10 km/h (the bike is placed with wheels up so the motor works without load). It's not easy to maintain this speed rotating the magnet ring by hand. Then small rotation increase causes a rapid increase in the displayed speed and you don't need to rotate much faster to reach the maximum speed (50 km/h). A small rotation decrease and the motor stops driving the wheel.
Fortunately, the included left PA sensor doesn't fit my bike so I also purchased a bigger right side sensor (exactly this one https://allegro.pl/oferta/czujnik-e...wojne-czujniki-hallowe-12-magnety-13905770397).
And bang! With this sensor everything seems to work much better. At the same highest assist level you can easily maintain 4 km/h rotating the ring slowly by hand and then easily increase rotation to display any speed you want. It seems that this sensor is much more linear than the one included in the kit.
I still didn't finished this conversion because the bolts on the motor on the disc brake side stick out too much. But I'm now more optimistic about this YCSY126 controller.
I would like to point out that I changed two things in the controller configuration: the number of assist levels from default 5 to 9 and the speed limit from default 99 km/h to 50 km/h (maybe it also matters).
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