One can start at Ponte delle Capre/Lago di Livigno (1809m) to the north and climb up a mostly cyclable gravel road to the pass (but have not tried this side myself!). One could also start in Bormio (1200m) and climb the many nice serpentines of what was once a rather dusty but easily cyclable road, that was asphalted around 2009-2010 (?) up to the Passo Torre di Fraele/La Bocchetta (1938m). The road is quite interesting, but try and avoid work hours as many heavy lorries use the road going to the big dam up there. Turn left a while after the pass and small lake and follow the road along the Lago di Cancano. It is quite funny with all the tiny warning signs at the beginning of the road. The road ahead is not flat even though it follows the lakes.

After some time you reach the next huge lake/dam, Lago di San Giacomo di Fraele, and you cross over its dam building (I doubt that the road ahead on the west side is cyclable). (There is also a road on the east side of Lago di Cancano, which is probably usable too.) Over on the east side, you should follow the road down to the lake. When you reach the end of the lake a road continues ahead (and later splits up) – right there is the Passo di Fraele (1952m). You should turn left and stay by the lake for ca. 500m until you are nearly back on the west side again, where you will see a gravel road/track going up among the trees. It is possible, but not easy, to cycle on at first, but much easier when it flattens out higher up. It is 4.8 km from the lake to the pass.