400bhp
Guru
In the absence of indicators, you should use your arms and indicate your intention before you make your manouver, and then that gives you time to make it with both hands on the bars. I'd call it good planning, and that goes along the same line as road positioning on a junction, ot turning right across a carriageway.
It's not always possible to do that - e.g if there are two turnings close to each other.
I think it was Greg Collins a while ago on here who said that he doesn't signal to turn left as you often get cars [who are waiting in the opposite direction to turn right into the road you want to go] taking a chance and pulling across you when they see you indicating to turn left (and to a lesser extent, cars overtaking you when you haven't finished your manouver). I think this is a very good point and I now generally take this stance.