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A comment on America’s Havana: Thousands Say “Ciao” to San Francisco.

Re:America’s Havana: Thousands Say “Ciao” to San Francisco by gorgoiler on Tuesday May 12, 2020 @07:36PM (#23161444)
The article brings up BART wheel/rail noise, which is an interesting window into SF’s unique and some might say self inflicted issues.

It’s my understanding BARTs screech comes from statutorily over-powered brakes grinding flats into the wheels.

The power rating didn’t take into account the fact that BART is both an all weather outside and an underground (dry) system. On wet outdoor tracks the indoors-only power brakes lock up and wear the wheels flat.

In turn these flats grind periodic indents in the tracks, and the whole thing has a feedback loop which ends up in the entire track being corrugated and no wheel ever being truly circular. Solid axles (no differentials) don’t help either.

Screeching and howling ensues to a level that is damaging to the hearing of passengers and staff alike.

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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by Gibbon1 on Wednesday May 13, 2020 @12:26AM (#23163477)
The flat wheel thing is a mistake that was made what, 60 years ago. Everyone involved is dead. They've been finally working on fixing it. Yeah BART could be a better built systems if only people long dead had made better choices.
[ Parent | on HN ]