I see lots of Amish on Greyhound busses. They tell me they are visiting family in other areas. Also they were bussing down to New Orleans to help out with Katrina relief.
I used to go to a farm auction in Hillsdale, MI. The Amish came in large numbers. They rode in with their neighbors, who happened to be Mexican farmers and farm workers. I thought this was an interesting example of cultural symbiosis. If they think it's OK to ride in a car with neighbors, why do some of us think it's wrong?
I have never seen an Amish person on a bicycle. I think the young adults sometimes spend a year or two outside the community. Maybe they ride bikes then? If so, it must be hard to stop when they go back....