I finalized my Cateye Strada cadence installation. The cadence sensor couldn't see the magnet when mounted on the frame, I had to shim it by a lot.
It's not the most elegant solution, and these photos are from the work in progress (it's actually aligned better now), but it's gonna do for the rest of the season. I used 2 layers of plexiglas, heated it to give it a curve similar to the frame, filed the edges and added a layer of electric tape on the back to prevent scratches. But it still wasn't enough, so I added a layer of pipe insulation foam, painted black. First suitable thing my eyes came upon in the shed.
To prevent wires rubbing and wearing under the tube, I slid them into a short lenght of wire loom.