The Valencia Street center bike lane is closed for around three months, meaning probably until June. What a mess. It seems odd that the entire center lane is closed while they work on just one section but so it goes. I would avoid riding a bike on Valencia Street and take the side streets or Folsom Street. I do not recommend Guerrero Street as that is a place were people often drive way too fast.
SFMTA News
https://www.sfmta.com/projects/valencia-bikeway-improvements
SFMTA News: What is happening now:
https://www.sfmta.com/projects/valencia-bikeway-improvements#2
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