The DGT (Directorate General de Trafico) has finished an exercise to grade the emissions of motorcycles, sidecars and quads. The majority (55%) will now fall into four distinct categories.
Zero emissions. This relates to battery operated vehicles or hybrid vehicles with an autonomy of more than 40 kilometres.
ECO. This category has been established for non-pluggable hybrid vehicles and for those that can be connected but have an autonomic range of less than 40 kilometres.
C. Vehicles that satisfy the homologation requirements for Euro stage 3* or Euro stage 4*.
B. A vehicle that meets the homologation requirements for Euro stage 2*.
With vehicles catgorised in this way municipal authorities will be able to adjust vehicle taxes to discriminate against those that pollute the most, for example.
It could also be possible for Cities such as Madrid and Barcelona, where pollution is a big problem, to only allow certain category of vehicles to enter the city centre.
It is totally voluntary but once you establish whether your vehicle fits one of these categories you can obtain a sticker which you can put on your bike. The stickers cost five euros from the post office.
The other 45% of similar vehicles are outside any of the four categories mentioned above.
*Euro stage 3/4/2 are regulated emissions standards introduced by the European Union at varies times. They are designed to reduce pollution.
(source: dgt.es, transportpolicy.net)