A tip for biking more safely. I always use two leads. One is hooked to it's own handle, making a circle that goes over my shoulder. This lead is looped through the handle of the second lead which is hooked to the dog collar. Hope that makes sense. If it doesn't I can put up a photo.This leaves both hands free for steering/braking and if the dog pulls it's pulling against your whole body rather than your hand..
The only time I had trouble holding this way is when a fox jumped onto the road in front of my 29 inch, 37kilo deerhound cross.
post picture if you can cheers