Hi, I am from Nigdi and generally cycle 20 km.s per ride!
One of my favourite routes is this - Nigdi - Talawade Road - Talawade - Dehu road - Dehu Gaon - Military Area - Mumbai Pune Road (Old) - Bhakti Shakti Chowk - Nigdi.
I love riding in Military area there - a stretch of 5 km.s approximately. The reason to love riding here is obvious - this being military area, the traffic is less & what ever traffic there is, has to be disciplined. This always proves to be the biggest relief from the shameless indisciplined traffic of Pune & PCMC. Of course, the relief proves short lived once you touch old Mumbai Pune highway.
Never the less, this stretch is enjoyable.
Following is the link to the route I take -
Talawade road from Nigdi Chowk is generally enjoyable in the mornings.