Replace cars with velomobiles
Replace cars with velomobiles

solar.lowtechmagazine.com
Electric Velomobiles: as Fast and Comfortable as Automobiles, but 80 times more Efficient

Speed record of a velomobile: 144 km/h https://www.aerovelo.com/eta-speedbike
We don't need any knew infrastructure, we just need to get cars out of the way