I must confess that I've used the 815s without bow or stern tie-downs, but my two kayaks have not budged at all. I peek at them through the moonroof on my car from time to time, and they've never shifted. It's important that you read the directions on how to secure the two strap assemblies. If you do it correctly, they will not loosen. Thule's buckle bumpers are pure genius for protecting your car and your boat. When I get home one night with only one kayak on the roof, I entered my garage before the door had fully opened. The bow of the kayak hit the bottom lightweight insulated aluminum panel of my garage door and crumpled it, but the kayak didn't budge (nor did it get damaged, phew!). However, in the interest of safety, I have resolved to use bow and stern tie-downs in the future. To this end, I have purchased and installed bow hood loops from Riverside Cartop Carriers on my car.
I managed to install one UpRide and 3 of the older style Thule bike racks simultaneously on one car (ie 4 bike racks). A total of 3 is relatively easy but adding the fourth bike required the pedals to be removed from the bikes and was quite a squeeze. If you are going to install 3 or 4 bike racks then you will need to alternate the direction in which they face (forward-back-forward-back) and you will need to ensure that the various closing mechanisms on each of the bike racks are relatively easily accessible. Good luck 😉 !
There are a few other things that are important to me, and no doubt many of you will have your own requirements depending on car and lifestyle. I for example like a rack that won’t take up much space when off the car – which pretty much rules out boot or tow bar mounted racks. I’d also rather leave it in situ for most of the time due to the amount of use.
Choose aerodynamic roof bars for superior performance and a sleek, sophisticated look that complements the lines of your car. These roof rack cross bars also have many smart design features. A textured surface disturbs the airflow and greatly reduces wind noise. The aluminium extrusion creates one of the strongest load bars in the market. The design gives you quick, no-hassle installation. While the end cap pivots and T-track make it easy to add further loading options.