Join Date: Feb 2007
Location: Tariffville, CT
Bikes: Tsunami Bikes
The holes are there so you can adjust where you mount the rack.
In general you want the crossbars pretty far apart. 25-30" would be fine. You can go to 16" but that's kinda short - the rack is plenty strong, the problem is that the car under it isn't - roof will dent or factory mounts may pull out.
You can mount one backwards.
You don't need anything else to secure the bikes. Lock/lever up front, strap in rear.
Here's a car with a lot of Inno stuff on it:
I helped install Inno racks on the JB cars and had the privilege of driving one to/from CA-NV. I also helped with Inno at Interbike for a couple years (unpaid). They have a good, well tested product. They test their products at Honda's high speed track at 200 kph (124 mph), on their bump track, etc. I have some mounts (yes I got a discount) and sold my other rack after doing some research/learning.