Different countries have different laws about what must be carried when driving or riding a bike there. It is worth taking a few moments to check the law in your destination countries and make sure that you don't run foul of the local plod.  Items such as first aid kits, hi-vis jackets, warning triangles and even breathalysers are obligatory in many European countries.  While this list is as up to date as we can keep it, checking with your motoring organisation or similar before setting off can get you the very latest information.