Re: The chase vehicle
Depends on the size of the group (5? 10? 50?), the bikes they ride (cruisers? touring? makes?), each bike's and owner's personal preparedness (tires good enough? oil level ok? range of clothing packed? etc), and some other factors.
Anything ranging from a full size pickup truck and/or panel van, to a large U-haul van with a large enclosed trailer.
Last year, while at the Gap, I ran into a large group of riders from Texas. A mixed bag of mostly Harleys and GoldWings, with some other bikes sprinkled in. Had to be about 30-40 bikes. They had a large u-haul moving van, that's it.