During a strike, the damage depends on the path through which the energy flows. In a steel-enclosed vehicle, you are protected because the engery will typically flow along the outside of the steel structure and then "jump" to the ground. On any vehicle that is not enclosed, such as an ATV or a bicycle, the path of energy flow with be through YOU.

From what I've read, the best thing to do is to seek shelter (building, car). If that is not available, then find a low spot and make every effort to be the lowest thing around. Stay away from trees, poles, or the like, since just being near a strike could cause injury.

Here are a National Weather Service's Lightning Safety Outdoors web site:

http://www.lightningsafety.noaa.gov/outdoors.htm

Here is a web site the gives first aid instructions for responding to a lightning strike - interesting triage (sp?):

http://www.utahmountainbiking.com/firstaid/lightng.htm