School me on roof rack bike carriers

Thule holding by the fork drop outs.

I have a roof system and a towbar rack, all from Thule. They are good quality but not cheap, although they come up second hand all the time (I bought my towbar rack from Facebook Marketplace).

Roof: you need two roofbars with the correct feet - a site like roofracks.co.uk will help you find which ones fit your car. The bars will clamp to your existing roof rails and are often lockable, usually an optional extra. There are various shapes of roofbar, from cheap square ones to expensive aero/wing shaped ones. I have the latter as they help keep noise down. You then need a bicycle rack. I use the Thule 592 which keeps both wheels on and clamps the downtube. I use it with MTB and road bikes, steel, alloy and carbon frames. It is easy to get the bike on and off, although is a bit of a reach on top of our XC60 (I can do it without a step and am 5’10”, but that is with the rack located to one side of the car). The rack fits to the bars either with a ‘T-rack’ system that runs along a slot in the top of the bars, or you can use a U-shaped clamp over bars with no slot. T-rack is cleaner and very easy to use; you get a rubber strip to fit in the slot to reduce wind noise. A roof rack limits which car parks you can use, although with planning ahead I have never been stuck for somewhere to park near where I want to be, and have never forgotten about the roof load and hit anything with it.

Towbar
I have a VeloCompact 927. As I said, picked up for a good price second hand. It’ll take 3 bikes as standard with an optional adapter to add a fourth. I have only used it for 3 (the 4th goes on the roof if needed). It is a very sturdy thing. It clamps the frame and holds both wheels. Fitting three bikes is a bit of a faff of lining up pedals, seats and handlebars and threading the frame holders through it all, but it is at waist height. The rack pivots down to allow access to the boot. It adds a significant rear overhang and length, making parking more tricky but if we use it out and about I usually unload the bikes then take the rack off and put it in the boot. Of course you do need a towbar and electrics fitted to your car.

All of the above are lockable but I don’t consider these to be secure - if I’m leaving the bikes on the car I use a cable lock for security.

I had a Thule roof mounted holder which worked fine, pretty secure and usual Thule quality. I quickly moved onto a tow bar system though. For me tow bar is a more secure mounting for the bikes (they are out of the wind so don’t get as much movement through the journey), it’s a lot quieter and just easier to get the bikes on and off. Most of the tow bar mounts come with a slide that allows access to the boot.

Take a look at roofbox.co,uk, they do a wide variety of both systems so you can compare. I’ve no idea whether they are good prices or not though.

I tend to agree, with the following additional comments:

The towbar rack needs somewhere to live when off the car - mine folds down but is quite heavy.
The rack can not stay on the car when not in use. Well, it can but it makes things awkward.
With the towbar rack on you lose any reversing aids on your car.

I use the roof for taking one bike anywhere, which is usually less than an hour’s drive. The rack stays on the car all the time, which will blunt fuel economy but as I use it most weeks it is easier than repeatedly fitting and removing it. I use the towbar rack for when we take all of our bikes anywhere and for any long journeys. If taking all 4 family bikes, my son’s 20” bike goes up top, for minimal drag.