The Hope V-Twin is fairly expensive and really isn't a dual pull adapter. You would still need a dual-pull cable lever.
Why not purchase a hydraulic cable splitter or an extra-long banjo bolt and go completely hydraulic? You can dial in the bias with different rotor sizes. 180mm front and 140mm rear should get you to around 65/35 bias.
I am going with a fully hydraulic scooter brake system with "ABS" bottles on my XR-80 build. These blow off excess pressure before causing a wheel to lockup. It seems that there would be less maintenance with a purely hydraulic system.
Because the master cylinder for hydraulic (bicycle) brakes is not designed to actuate two brake calipers; causing a spongy feel at the brake lever if trying to move twice the fluid volume.
Because the master cylinder for hydraulic (bicycle) brakes is not designed to actuate two brake calipers; causing a spongy feel at the brake lever if trying to move twice the fluid volume.
If you purchase a high-end master cylinder, especially with adjustable throw, this is not an issue. The smaller piston area actually helps improve modulation and reduces throw effort.
You can also always purchase a scooter master cylinder (~$40) and grab compatible brake lines.
See this brake bias calculator. It is designed for cars but the principles are the same.