Edited by Pete on November 23, 2017, 10:13 am
The flat bit on the wheel that runs on the rail isn't flat, its shaped to guide the train on the rail better than it used to and that's why they don't rock side to side like they used to. Keeps the coffee in the cup so much better.
This meant they had to move from rim brakes to discs No bad thing as they stop better and better acceleration and deceleration means faster journeys.
Now the problem: The leaf mulch on the rails gets on the wheels and isn't scraped off by the rim brakes any more. The trains can't stop as well and they have to operate at lower speeds.
All because you didn't want to spill your coffee