Bore Measurments In Manual

Hi

I have recently acquired a 1971 Triumph Tiger 650 (TR6R) which has been sitting in my uncles shed in bits since 1979. I am assessing the engine components, and don't understand the 2 measurements given in the Triumph manual. For example, for Bore Size, it states 2.7948"/2.7953". Is this a range (min to max) ? Sometimes, the measurements are the other way round - for example Piston Top Of Skirt Clearance 0.106/0.0085. Can anyone help clear up my confusion. The metric alternatives are also shown as two numbers separated by a "/". Many thanks, Simon