Out for a bimble in the sunshine yesterday afternoon and a fellow biker passing by the other way stuck his arm out and put his thumb down at me in a very distinctive way, he was definitely trying to tell me something.....

Is this a "recognised" signal?

Was he trying to warn me of something?
Was he dissin' my ride?
Was he lovin my ride and it's his way of letting me know?

Or have I missed the memo completely?