As currently configured, these cars have large spaces between the last row of seats and the end of the car. This space is frequently used for bikes in Illinois and Missouri. This practice can be expanded to all low level trains with no cost. Bike racks can be added to this area as cars are rebuilt. It could be a simple as installing a standard seat belt in order to restrain the bikes.
Several manufactures make racks suitable for use on trains.
These calculations are extremely conservative. The Cardinal does not indicate the true potential of bike racks. It has experienced low ridership levels because it does not run daily, has slow running times and has poor schedule keeping. The bike service has been poorly promoted. Making roll-on service universal will also cause the ridership on individual trains increase since riders can then connect between various trains.