Originally Posted by
Looigi
Get a 3x12mm or 1/8"x 1/2" rare earth magnet and stick it to the back of the crank arm with double stick tape or put it under a piece of gorilla tape. With duotrap, you're stuck with where the magnet has to go. With sensors that mount on the stay, you can often let the magnet stick to the inside end of the pedal spindle and align the sensor appropriately.
That's what I'd do. With the Duotrap arrangement, you might as well just stick the magnet down with double sided tape. You can find magnets of any size and shape on Amazon.
J.