Originally Posted by
bbrase
The 1/2" diameter fits almost perfectly on the inboard end of the pedal spindle when fully inserted into the crank arm. Even if your pedal spindles aren't long enough to go fully through the crank arm, these magnets are strong enough to lock in place there and not move. Stack a couple of the magnets on top of each other (or get the 1/8" thick ones) to increase the strength and close the gap to the sensor a bit.
Now *that* is a slick idea!
On my road bike, the crank is so far from the chainstay, that I had to carve a section from a 1"
wooden dowel rod to lift the magnet nearly 1/2" to get it close enough to the cadence sensor.
It looks kludgey.