A quick search didn't help me find the answer so I thought I'd ask it directly...
When riding on a trail or on a narrow-enough road that you can look at an on-coming riders face, is there a generally accepted acknowledgement that their part of the riding community?
My frame of reference is with motorcycling. In general, any time you have an on-coming rider approaching you it's accepted that you'll drop your left hand off the bar and "waive". It gets a little less certain if you have a sports bike riding toward a Harley as the riders are part of different biking cultures but it still happens and is something you get used to doing.
So far I haven't seemed to experience any consistent acknowledgement and wanted to see if it just isn't part or the culture or perhaps I haven't learned the secret handshake yet.