Are they the same type and diameter?

Do I need to unwrap my bars to change inner gear cables [SRAM]? It's been about 16K kms and I need to adjust the cable tension almost every ride. Have a feeling that it is fraying inside.

Thanks guys.

At that amount of use I would recommend replacing the housing as well as the cable...Both cable and housing are the same for SRAM and Shimano...

Cables are, 1.6mm for brakes, 1.1mm or 1.2mm for shifters. The cables have different ends so that helps to figure out which is which.

Housing is 5mm for brakes and 4mm or 5mm for shifters. Again, there is brake housing and shifter housing, they are not interchangeable. For the shifter housing you can use either the 4mm or 5mm, but for some bikes with internal cable routing the cable stops are designed for 4mm only. I'd say to replace the housing with the same size housing you currently have.

I agree, I'd replace the housing as well as the cables. However, it is possible to replace cables with the previous housing still wrapped inside the old bar tape. It may get a bit tricky coming out of the shifters as you try to feed the cable end into the first bit of housing.

Thanks guys. Found out yesterday that the LBS has Jagwire sets, so am changing housing and inners today. Usually tough to get these things easily in India, and thought I would have to order from UK online stores as usual.