Thank you all for the suggestions. I have completed the trip. While going I choose Bangalore->Mysore->Gudalur->Nilambur->Perinthalmanna->Pattambi->Kunnamkulam->Guruvayoor. The roads in these road is good,scenic view. It was heavily raining in Gudalur and visibility was limited to some feet. It took some time to cross Gudalur ->Nilambur even though the road was in good shape. Only I experience bad road at Pattambi due to a road consruction happening. As I had planned to go to Ernakulam, I choose return via Ernakulam ->Aluva->Angamaly->Thrishur->Vadakanchari->Shornur->Palakkad->Walayar->Coimbatore->Annur->Avanashi->Salem->Darmapuri->Krishnagir->Hosur->Bangalore. The roads at Walayar are tarred and in good shape.It was my bad decision to enter Coimbatore town, and got stuck in traffic 1 hour. There was some bad stretches before entering the toll road at Avanashi also. The roads from Avanashi to Salem is excellent and from Salem to Krishnagiri it was ok road ;6 Lane conversion is in progress at these area.From Krishangiri it was again slow moving traffic due to the road work and rain.