>>20282842nd wave fixie culture was heavily tied to late 00s hipster culture and because of that, it was inherently a grassroots oriented culture. 3rd wave fixie culture by contrast weighs far more into social media, influencer salesmen, clout, and especially a lot more into consoom. The bikes of 2nd wave were more salvaged old ten speeds converted to fixed gear and at the tail end of their era, progressed to track bikes for the street ("tarck" bike). 3rd wave picked up from track bikes for the street but sought to fit the widest tires possible which lead to the wide tire fixed gear frames we have today.
>>2028286exact years differ city to city and country but generally 2nd wave was late 00s to early 10s and 3rd wave is late 10s to the past year or two ago, 3rd wave just about finished. Additionally, OG fixed gear era is Henry Desgrange era, and 1st wave is Sheldon Brown era. I believe those are the years