Updated: Nov 28, 2019
Whilst travelling in other countries you can carry your bikes on your car's roof-rack, making sure they are attached to an adequate roof-rack and the total height doesn't exceed 4m.
You can also carry bikes on the back of your Motorhome/Caravan providing they do not obscure your lights, number plate or indicators.
Check the countries requirements as in some countries like Portugal you must make sure you carry your bikes on the rear of your leisure vehicle and not your car.
Note: - Bikes may be rested on the tow bar providing the tow bars maximum weight is not exceeded. In some countries marker boards must be fitted even if you are not carry bikes or the bikes are folded.
In Spain and Italy, any overhanging loads must be indicated by a rear marker board measuring 50 x 50cm with reflective red and white diagonal stripes. These boards are available in both aluminium and plastic, from most accessory shops. The boards must be fitted with the stripes pointing towards the offside of your vehicle. Some boards can be rotated when travelling through other countries.
In Spain you can use either plastic or aluminium boards, but for Italy the panel needs to be aluminium.