Bicycle hydraulic disc brake proportioning valve

Mechanical engineer required to design and manufacture a break pro portioning valve to enable shimano Road hydraulic ultegra/dura ace and XT mountain front and rear caliper brakes to operated safely from a single (1) brake lever. The prop valve has to be manufactured in a compact lightweight design and pass euro standards and be fully compatible and functioning with the shimano hydraulic systems. This product is to be fitted to disabled, single arm rider bicycles as such the front and rear brake systems have to operate together from the one lever but also safely balanced with equal modulation so neither rear or front brakes lock prior to each other which would result in unsafe braking. Cad and solid work drawings are required, a3d printed vprototype and an actual working sample of the product are required for review before an initial production run of 20 units are produced.