It's a long way up there when you have a full size Chevy van. The bikes
would stick up higher than the trailer's A/C.
If I had a rooftop carrier then I'd have to find a place to keep the
ladder. Also I don't have 15# bikes - the Mondia is 23+# and the
Cannondale is 26+#. The Fuji knock-around bike is over 30# and who knows
how much the gas pipe (or maybe solid bars of iron?) huge Schwinn weighs
(grunt!). The lightest bike I ever had was the much lamented late Gitane
TdF that was 21# (squashed by a Dodge van).
I want to get an enclosed bike carrier to go on the back of the trailer
for lack of any better place. The front of the van is not a good place
for an enclosed carrier, as it would block the radiator and lights.
Al
Bike rider for 46+ years