BART is turning 40 and offering San Francisco residents a birthday present of their own.

For every Friday in August, the transit agency will allow passengers with bikes to board at every station, onto every train, at any time.

"It's all day, all trains," Steve Beroldo, BART's bicycle program manager, told the San Francisco Chronicle.

(SCROLL DOWN FOR PHOTOS)

Normally bikes ares banned from BART during commute hours (7:00-9:00am, 4:30-7:00pm) on weekdays on every line except the Richmond-Fremont.

Many of these cars are too crowded to accomodate bikes. But commuters have complained that it discourages them from biking to work and from taking BART.

"I often have multiple stops and I need my bike on the other end,” Adina Levin of the Silicon Valley Bicycle Coalition told KQED. “Bringing your bike on board gives you 16 times as much access as walking, you can get 16 times as far, so it’s a really powerful tool.”

BART plans to survey riders' experience with the new system using both its website and postcards handed out at stations. It will also collect reactions from station agents, train operators and other employees and will analyze any possible delays or increased amount of time trains may linger in stations.

During experiment, bikes will still be banned from the first car and from escalators, and bicyclists are urged not to try to wedge themselves into already packed cars.

"The message is to be respectful and use common sense," said Leah Shahum, executive director of the San Francisco Bicycle Coalition. "If there's not enough room, wait for the next train."

Scroll through the slideshow below to see people behaving badly on BART, and then let us know how ending the ban will affect your commute in the comments:

Loading Slideshow...
  • "This woman was too preoccupied in chomping on her overpriced Whole Foods salad to move her bags off of that empty seat".

  • "This guy literally elbowed my 5-year-old daughter out of the way to sit down, while we stood from West Oakland to Walnut Creek. Sure hope that seat helped him score an Angry Birds personal best."

  • "Really wanted to sit right next to her just to piss her off".

  • "This guy was covered in sh*t down his backside. Somebody will eventually sit in the fabric seat he was sitting in".

  • July 7, 2012. This d*ckhead was wearing spurs. I don't give a sh*t what kind of fashion statement he was trying to make. Imagine him backing into you on a crowded train and stabbing your Achille's tendon?

  • "Look at the reflection of the guy across from Mr. Stinky Feet - he's gagging"

  • "Excuse me sir, you dropped something!"

  • You shall not pass.

  • "This fine gentleman who is manicuring his fingernails on a crowded train. I almost lost an eye".

  • "Mmmmmmm Starbucks"

  • "Give the elderly gentleman a seat!"

  • "Packed train after a Giants game and we got a double whammy here: a sleeping guy and a luggage lady. Meanwhile, it's standing room only."

  • "Ooh my backpack is too fancy for the floor..."

  • "Riding home on a packed train after the Giants game and this guy decides to make himself comfortable."

  • "Barty Appleseed"