Had my first puncture since fitting Thorn kits, thinking of changing to Schwalbe Marathon Tyres. My bike at present has Schwalbe Marathon Racer 26 X1.5, this is the tyre that punctured, my wife's bike has Continental Sport Contact 26 X 1.3. Both bikes have mudguards. My wife has slight arthritis in the hands & is feeling the road bumps, I therefor would like to increase the tyre size. Does anyone know the actual height & width of 1.5 & 1.75 sizes so that I can check if they will fit.