Minorca might be a small island but there is plenty of good biking to be had. The Camí de Cavalls coastal path provides some great singletrack riding and some fun downhills. It makes a complete circuit of the island and is well marked by posts so you don't need to lose time map reading. Some sections are quite well transited but on others you will rarely see another person. Some sections are technically pretty difficult and will require the occasional bit of pushing or carrying. To plan your route just pick a section and ride it! Maps and more info here: http://www.cime.es/ca/cami_de_cavalls/index_pe_camidecavalls.html (links in section 5).
There are 6 good MTB routes published on the http://www.illesbalears.es website. These are also well signed and easy to follow:
- Route 1 Ciutadella - Ferreries. Distancia 16,5 km. Duración aprox. 1 h. Dificultad, fácil. [img_assist|nid=413|title=BTT Coast path|desc=|link=node|align=right|width=150|height=113]
- Route 2 Ferreries - Es Mercadal. Distancia 15,5 km. Duración aprox. 2 h. Dificultad, media.
- Route 3 Es Mercadal - Alaior. Distancia 7,7 km. Duración aprox. 1/2 h. Dificultad, fácil.
- Route 4 Alaior - Maó. Distancia 12 km. Duración aprox.1 h. Dificultad, fácil.
- Route 5 Maó - Es Castell. Distancia 8 km. Duración aprox. 40 h. Dificultad, fácil.
- Route 6 Es Castell - Sant Lluís. Distancia 6 km. Duración aprox. 1/2 h. Dificultad, fácil.
Consult http://www.illesbalears.es/esp/menorca/cicloturismo2.jsp?SEC=CTU&id=0000... for more information and download the maps, which only seem to be available in Spanish.
There are hundreds of kilometres more of paths, tracks and minor roads that are great for riding and waiting to be explored. There are a number of good bike shops on the island for spares or more advice.