Firstly, there are two sources of professional advice you have available to you concerning roof racks. Your car’s manufacturing company will often have put together a list of recommended roof-rack models and suppliers, with fitting information and particular concerns that may be relevant. A quality manufacturer should not have a problem with discussing these kinds of things with you, so try giving them call.
Your second source of advice is your local roof-rack shop. A well-established business will offer impartial advice designed to get you and your bikes on the road safely and securely. However, even when taking advice, it’s good to have some decisions made beforehand, and to be aware of the safety and ergonomic considerations involved in choosing the right rack.
Load – Are you likely to need to carry more bikes in the future? If your family is going to grow, or you’re likely to get friends involved in biking and will need to transport more than you do presently, be sure to select a model with a flexible carry-load.
Car Model – It’s highly unlikely that you’ll find one bike rack to fit two cars, so if you have more than one car choose which one you are likely to want to use. If you are not taking it to the bike rack shop, note down all the make and model details and take them with you.
Durability – Spend money based on how long you want it to last, quality racks will last years, but if you only want it for a few one-off trips then buy in the lower price-range.
Positioning – You’ve got a few choices (depending on your car make and model) of where to fit the rack. Some areas are common sense, and some add extra functionality or access to your car. Here’s a run-down of the different ways a bike rack can be positioned, and details on the pros and cons of each.
Front bumper racks: Not normally recommended, and only suitable for vehicles with a high front-end. If positioned too high they can interfere with driver’s vision, and they also collect every single bug you come across on your way down the motorway. You will also need to check that these kinds of racks are acceptable in your area, as they are illegal in some areas and countries.
Roof mounted racks: A secure position which will carry at least 4 bikes, and can take many more depending on your vehicle. The rack can also provide a surface for attaching a roof-box, which can carry luggage, sports equipment and your bikes under cover. This method of carrying can also prevent damage to the bikes with the upright, clamped position. You’ll pay slightly more for the benefits of this bike-rack, and may have to use a small ladder to actually get your bikes off and on to the set-up.
Vehicle-rear racks: The most common form of rack used, you can normally carry about 3 bikes, and the rack is attached using straps and metal hooks. Bikes are often very close together, and the use of foam pipe-insulator as a protective wrap is recommended. Bikes must be securely strapped to prevent bounce, and access to the boot is often completely cut off.
Tow ball mount: Installed with a square mounting post inserted into a square pipe bolted to the underside rear of your car – these tilt down when empty to allow for tailgates and rear doors. If you want one that can tilt down while loaded, you’ll need to pay extra for a load-bearing model. You can get 2 to 5 bikes on the bike rack.
Rear ball-hitch racks: This set-up can usually only carry a maximum of 2 bikes due to weight limitations, and usually clamps onto a hitch-ball or bolt through the hitch-ball mounting hole on the bumper or hitch tongue.
On a camper: Some roof-mount racks will adapt to a camper roof, and you can also get ladder-mount racks for the rear. There are some receiver hitch racks that fit in between the back of your vehicle and the front of your camper. A roof mount or ladder-mount would be the best choice. Some people simply strap their bikes to the roof, but you can easily damage the fibreglass so this is not recommended.
Sports car interior: You can get brackets to ensure your bike doesn’t shift around when carrying it inside your vehicle, and presuming you have enough room this is a cheaper and safer option (less chances of thieves getting their hands on the bikes).
It’s also a great idea to make use of all the magazine and Internet sources out there constantly testing roof rack and roof-bars to find the best option. For example, this article targets the 6 best roof-bars, and this site provides customer reviews of bike-racks.
Overall, the two best choices are the rear bike-rack and the roof-mount. If you know you’re only ever going to be transporting bikes, and want to be able to free them quickly and without fuss, a rear hitch rack may well provide the speed and flexibility you need. If you may be wanting to transport luggage, snowboards, skies or other paraphernalia in the future, a set of roof-bars and a roof-box are the best idea. They provide all-weather protection and security for whatever you want to carry, and can be left on the car without making any doors inaccessible. Thule is leading the way with roof-bars and roof-boxes at the moment (although you do pay a little extra for that quality), so take a good look into their models.
And finally, now you have the basics in mind and have likely decided what type of bike-rack you are looking for, find a reliable dealership to ask advice or track down the best deal on the Internet and email them for recommendations and help.