Originally Posted by HillRider

Cat-Eye used to sell the "Astrale" a wired computer with a rear wheel pickup for speed/distance and a cadence pickup so it would work fine on a trainer. The pickups were fastened to the nds chainstay and the magnets mounted on a rear wheel spoke and non-drive side crank arm. I have had one on my trainer bike for several years. The Astrale is discontinued but Cat-Eye still shows the "Strada Cadence" on their web site that seems to be a newer version of the same thing.

I wonder if wireless computer heads will pick up the signal from a rear mounted magnet and pickup. Any body tried it?

Yes, I've noted the rear wheel pickup gives a slightly shorter distance reading than a front pickup but the deviation is about 0.5% by my measurements, certainly not 3%.