It turns out if you take the wheels off the tandem fits perfectly on the back of my bike rack and the ends stick out as far out as my mirrors. I put a bungee cord on the fork to keep it place because I don't want the handlebars to stick out when am I driving down the road. Now Katie and will be able to try more rail trails and other places to ride.
It turns that this bike has a 1 1/8 threaded fork and I am going to find a squishy fork with a lock out and disc tabs. I'll get a set of Atom Blast wheels and better off road tires so that Katie and I can start riding more gravel grinder routes and some single track, too. I think we'll also need to throw on some Crank Brothers pedals and I will get her riding, clipless, too!