To transport a bike on the roof of the car is a truly practical solution. The bike stays securely mounted and gets less dirty there than when transported on the rear door or towball.
Perhaps you don't have a towbar fitted, or want to use it to pull a caravan or trailer instead.
The only thing you have to worry about when using one of our Thule, Mont Blanc & Automaxi Roof Mounted Cycle Carriers is forgetting all about it when driving into your garage...