I just bought my wife a used Trek Madone 4.5. It has Shimano 105 cranks and has a duotap cadence/speed sensor but the cadence doesnt work. I discovered that the magnet is not close enough to the sensor. I took that magnet off the crank and move it closer to the magnet and it picks up. The magnet is the rubber band type that slips over the crank arm. Can someone suggest a different magnet that may be closer to the pickup.
If there is more room for the rubber to stretch, perhaps inserting a wedge on the inside of the crank.
You can also try neodymium magnets, pretty cheap on Amazon.
I had the same problem. I got a rare earth magnet and it just sits on the outside of the rubber holder with the original magnet on the other side. I’ve never had it fall off.
I use rare earth magnets on my pedal spindles. Haven’t had any problems with cadence on my madone 4.5
I use rare earth magnets on my pedal spindles. Haven’t had any problems with cadence on my madone 4.5
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There is a 5mm magnet band and a 10mm magnet band. If you have the 5mm one you might want to look at picking up the 10mm instead.
Chris
I use rare earth magnets on my pedal spindles. Haven’t had any problems with cadence on my madone 4.5
^+1
No experience with the duotrap & positioning, but I use neodymium on the pedal spindle of all three bikes.