Is the a way to change the friction values for a route? I have noticed that there is quite a difference between different routes. I have tested the vR 120 + 9 carriages and on the Münster-Bremen route I can normally apply full power (300 kN) but running the same train on the Berlin-Leipzig route (same season and weather, summer + AP cloud) the train starts to slip at about half power. As the consist, season and weather is the same it must be something route specific?
Make your tests on the same gradient on a straight run of track. Sharp curves can cause increased drag. The steeper the grade the more effective drag is imparted by gravity.
Did you run both tests with starting the game from scratch, loco coupled from the get go? I've had sessions inheriting stuff from the previous (most obviously rain on windshield), which is somewhat intended (for relay scenarios) but it can also have some additive effects like consist weight adding up (the calculation itself is nonsense but it exists, so).
A route has no such thing as friction. Steel rails are steel rails. Friction is defined per loco and basically depends on its weight (simplified in TS as stock dry/wet/snow parameters), and weather (humidity) changes it. AP Weather implements a more realistic effect the weather has on friction. Like Andras said, test after restarting TS.
