I recently got this rack for free. Someone down the street had left it outside with a “free” sign. How do I actually use it? Do I need to buy straps to hold the bikes down? Am I missing a part? It seems like the bikes would immediately bounce out of the indents without any retention.
Yes you must get something like a strap to hold the bikes in place. Something that you can tighten down to retain the bike and will not loosen. Nylon webbing straps with a tensioner are usually supplied with the rack when new.
A bike lock could do double duty in retaining and securing the bike, but something that can be tensioned is preferable. Consider a strap and a lock for true zen-like peace of mind.
Bikes on these kinds of racks are surprisingly stable, but must be secured; when transporting anything on our vehicles we must ensure very little can go wrong.
I was hoping to find installation instructions for your rack with factory tie downs.
You have a Hollywood Racks HR600/610 from around 2000. 2002 was the last year for a Traveler rack with arms like yours
Back then Hollywood Racks didn't have installation manuals on the web
3 and 4 Bike Models Available
Traveler is one of our most affordable hitch mount rack systems. Assembles in just minutes, includes No Wobble lockable hitch pin and tilts down for easy cargo access. Available for 1-1/4 & 2" receiver hitch.
The rack didn't come with any tie downs. The other answers have great suggestions for fashioning your own tie down system
Best thing is use a couple of bungy cords to hole the frame to the horizontal bars. A strop to stop the bikes slopping around, wraped around the upright post to stop the bikes sliding backwards should also be used as bungies are not the most reliable.
When tieing a bike down make sure it does not movve in a way that will cause damage, especially to things like deraileurs and (if a MTB) fork stancions. 'Shuttle rash' is almost inevitable when carring bikes on these racks.