Wheel encoder options.

I’m looking to see what’s available for wheel speed encoders these days.

I know there is the KOP encoder that fits to the KOP gearbox, but we had bad experiences with that gearbox last year (gears grinding themselves to death).

I see that Banebots has an encoder that fits their P8 gearboxes, but (once again) those gearboxes are backordered.

I thought of using the new mag sensors as a tacho.

Any other options out there for rpm measurement (with quad encoder outputs) that have a reliable mounting mechanism?

Note: Our transmission will probably be direct drive, so there is no chain or belt to make use or an idler wheel.