BDSM Street Fair -- Instagram Not Down with Dominatrix Pics (PHOTOS)

Whips and chains are all the rage in San Francisco today (most days, really) -- but Instagram ain't down with the BDSM celebration.

The Folsom Street Fair -- San Fran's annual BDSM and leather subculture festival -- is being heavily policed by the social app. The reason is pretty obvious ... there's a ton of nudity at the event, and apparently several inappropriate photos got posted, at least temporarily.

Instagram put up a disclaimer saying certain pics had been removed.

Here's the thing ... the ones that were deemed kosher are still pretty over the top -- unless you're used to seeing dudes wrapped head-to-toe in chains and leather thongs.

If you're not used to it ... here's your chance. Enjoy!.