I see that hand signals continue to be a topic of interest on some biking blogs. We all know the basic signals (As in the diagrams on the linked page, I signal a right turn by pointing my right arm straight out — I think there’s less chance of confusion).
But this discussion got me wondering about a motion I see on some group rides. Cyclists will put their (usually) left hand down when signaling slow or stop, and waggle the hand if they’re pointing out road debris.
But sometimes, they’ll move the left hand to the small of their back. And sometimes, they’ll hold it there stationary but other times, they’ll move it back and forth, as though they’re pointing to the right with their left hand — behind their back. To make matters more confusing, sometimes they’ll do the same signal with their right hand.
I’ve read that this can be considered an alternate sign for stop, but I don’t think so. I think it’s to indicate that bikers should move over to avoid an upcoming obstacle — for example, if a car is parked in a bike lane and we have to move left into the traffic lane to get around it, the signal would be made with the right hand.
But I’m just guessing. I haven’t come across any explanation of this signal in biking books or online. Because it’s a non-standard signal, it can cause confusion. And confusion can cause problems. What do you think? Is this a hand signal worth keeping around and promoting, or is it one best done away with?