4 ms·

I had wanted to do an analysis like this too -- had even recorded the trace of acceleration using iPhone during rides. But the main thing I thought would be us

I had wanted to do an analysis like this too -- had even recorded the trace of acceleration using iPhone during rides. But the main thing I thought would be useful would be to overplot the acceleration levels of other train systems in the US and Europe/Asia for comparison. Caltrain is simply an embarrassment to ride and realize this is what the center of global tech has to put up with. I swear a visitor from any other country with a reasonable rail system would ride Caltrain and think the train was about to shake itself apart. (Yes I realize the old silver gallery cars are especially bad while the Bombardier ones are better) Even if the gross level of shaking were resolved, Caltrain and most other trains we put up with here are so incredibly loud compared to other more advanced systems. You go to Germany, and even their subways (subways!) are so quiet as to feel self-conscious when you're talking on them. And in the meantime BART -- despite being designed well into the 2nd/3rd generation of US transit systems -- screeches along due to poor rail maintenance.

ummonk 7y ago
Funny, I hate the BART screeches so much that I consider Caltrain great in comparison. Guess I'm in blissful ignorance of what is possible. Hopefully the switch to electric trains in a decade will make Caltrain better.
- supernova87a 7y ago
  Well actually, I've been told that the problem of rail noise comes from improper maintenance of the rail track, not the motive nature of the cars themselves. Rail requires periodic grinding to be maintained properly. When you see rail and wheels riding "flat" on each other, that's actually not how it's supposed to be -- that kind of maximum contact actually produces the squealing because the surface area has lots of opportunity to make friction-induced noise. Supposedly, when you see a rail that's completely shiny on the top surface from being worn down, that's a sign that it hasn't been properly maintained. A properly ground rail and wheel actually is only interacting on a very small edge of contact -- and this is what produces a quiet ride. A properly maintained rail will be quieter than almost any other mode of transport (noise from the contact surface). It takes active rail grinding though. So actually, just a change to electric cars will not maintain quiet operations (although in the beginning I'm sure the newness of it will help). BART/Caltrain actually need to conduct the rail maintenance in order to keep it quiet. Unfortunately, whether it's due to budget priorities being elsewhere, or an indiscriminate customer who puts up with this, unless that aspect changes, we'll be back in the same place. I don't even know whether the conductors -- the ones who would be among the first to notice such issues -- are even trained to understand this. I encourage anyone to go ride the high speed rails of Germany, France, Italy, China, Japan, Korea, to understand what properly maintained rail is capable of feeling like. Or even the U-bahn in Munich, Frankfurt, too.
  - inferiorhuman 7y ago
    Well actually, I've been told that the problem of rail noise comes from improper maintenance of the rail track, not the motive nature of the cars themselves. Noise on BART is due to a liberal application of NIH. BART literally reinvented the wheel – they used flat profile wheels (nobody else does this) which dramatically increased noise and wear. BART also spaced the tracks too tightly in turns further increasing noise and wear. They made their cars out of aluminum to save weight, creating a bit of an echo chamber (this got worse once they removed the carpeting). Caltrain doesn't have the luxury of lightweight rail cars since they share tracks with freight service. BART doesn't bother greasing the tracks like nearly every other rail system (almost certainly an artifact of their homebrew train control system). Unfortunately while reinventing everything they opted against decoupling the wheels from each other (a.k.a. using a differential like a car or truck might). Oh and let's not forget the Oakland Wye, BART's testament to noise, poor service, and political dysfunction. Simply put BART can't really grind the rail fast enough to keep everything quiet for a meaningful period of time (if they could I assume the wear on the tracks would be astronomical). BART also needs custom rail grinders and whatnot because hey why not throw a custom track gauge into the mix. So actually, just a change to electric cars will not maintain quiet operations Caltrain is fairly quiet, at least inside. At the very least the electrification will certainly help with noise while stopped at a station. I encourage anyone to go ride the high speed rails of Germany, France, Italy, China, Japan, Korea, to understand what properly maintained rail is capable of feeling like. Or even the U-bahn in Munich, Frankfurt, too. Spain is missing from your list, they were instrumental in getting the Pendolino developed and, IIRC, have more high speed track than any other European country.
    - ummonk 7y ago
      Oh and let's not forget the Oakland Wye, BART's testament to noise, poor service, and political dysfunction. Is that worse than the SFO Wye? Samtrans had to create a bus shuttle from Millbrae to SFO because the BART service is so useless for traveling between Caltrain and SFO most times of day.
      - inferiorhuman 7y ago
- scrumbledober 7y ago
  I recently had a conversation at work where I commented how great Caltrain was since I used to commute on BART. My foreign-born coworkers all laughed at me. I look forward to riding some nicer train systems in the future.
privateSFacct 7y ago
Yep - having travelled a lot in Europe it is crazy how quiet some trains there are. Some just have a very light tick tick sound
mc32 7y ago
Yep these are built by Rohr, Alstrom or Bombardier. People who build rolling stock. The issue is due to insufficient wear leveling, the tracks cause noise (the non independent (fixed) axles cause small wave-like wear on the track surface in track turns which in turn cause the screeching. The fix is independent wheels, conical wheels or more frequent leveling of tracks.

ummonk 7y ago

Funny, I hate the BART screeches so much that I consider Caltrain great in comparison. Guess I'm in blissful ignorance of what is possible. Hopefully the switch to electric trains in a decade will make Caltrain better.

supernova87a 7y ago
Well actually, I've been told that the problem of rail noise comes from improper maintenance of the rail track, not the motive nature of the cars themselves. Rail requires periodic grinding to be maintained properly. When you see rail and wheels riding "flat" on each other, that's actually not how it's supposed to be -- that kind of maximum contact actually produces the squealing because the surface area has lots of opportunity to make friction-induced noise. Supposedly, when you see a rail that's completely shiny on the top surface from being worn down, that's a sign that it hasn't been properly maintained. A properly ground rail and wheel actually is only interacting on a very small edge of contact -- and this is what produces a quiet ride. A properly maintained rail will be quieter than almost any other mode of transport (noise from the contact surface). It takes active rail grinding though. So actually, just a change to electric cars will not maintain quiet operations (although in the beginning I'm sure the newness of it will help). BART/Caltrain actually need to conduct the rail maintenance in order to keep it quiet. Unfortunately, whether it's due to budget priorities being elsewhere, or an indiscriminate customer who puts up with this, unless that aspect changes, we'll be back in the same place. I don't even know whether the conductors -- the ones who would be among the first to notice such issues -- are even trained to understand this. I encourage anyone to go ride the high speed rails of Germany, France, Italy, China, Japan, Korea, to understand what properly maintained rail is capable of feeling like. Or even the U-bahn in Munich, Frankfurt, too.
- inferiorhuman 7y ago
  Well actually, I've been told that the problem of rail noise comes from improper maintenance of the rail track, not the motive nature of the cars themselves. Noise on BART is due to a liberal application of NIH. BART literally reinvented the wheel – they used flat profile wheels (nobody else does this) which dramatically increased noise and wear. BART also spaced the tracks too tightly in turns further increasing noise and wear. They made their cars out of aluminum to save weight, creating a bit of an echo chamber (this got worse once they removed the carpeting). Caltrain doesn't have the luxury of lightweight rail cars since they share tracks with freight service. BART doesn't bother greasing the tracks like nearly every other rail system (almost certainly an artifact of their homebrew train control system). Unfortunately while reinventing everything they opted against decoupling the wheels from each other (a.k.a. using a differential like a car or truck might). Oh and let's not forget the Oakland Wye, BART's testament to noise, poor service, and political dysfunction. Simply put BART can't really grind the rail fast enough to keep everything quiet for a meaningful period of time (if they could I assume the wear on the tracks would be astronomical). BART also needs custom rail grinders and whatnot because hey why not throw a custom track gauge into the mix. So actually, just a change to electric cars will not maintain quiet operations Caltrain is fairly quiet, at least inside. At the very least the electrification will certainly help with noise while stopped at a station. I encourage anyone to go ride the high speed rails of Germany, France, Italy, China, Japan, Korea, to understand what properly maintained rail is capable of feeling like. Or even the U-bahn in Munich, Frankfurt, too. Spain is missing from your list, they were instrumental in getting the Pendolino developed and, IIRC, have more high speed track than any other European country.
  - ummonk 7y ago
    Oh and let's not forget the Oakland Wye, BART's testament to noise, poor service, and political dysfunction. Is that worse than the SFO Wye? Samtrans had to create a bus shuttle from Millbrae to SFO because the BART service is so useless for traveling between Caltrain and SFO most times of day.
    - inferiorhuman 7y ago
scrumbledober 7y ago
I recently had a conversation at work where I commented how great Caltrain was since I used to commute on BART. My foreign-born coworkers all laughed at me. I look forward to riding some nicer train systems in the future.

privateSFacct 7y ago

Yep - having travelled a lot in Europe it is crazy how quiet some trains there are. Some just have a very light tick tick sound

mc32 7y ago

Yep these are built by Rohr, Alstrom or Bombardier. People who build rolling stock. The issue is due to insufficient wear leveling, the tracks cause noise (the non independent (fixed) axles cause small wave-like wear on the track surface in track turns which in turn cause the screeching. The fix is independent wheels, conical wheels or more frequent leveling of tracks.