My take is that if a dog is really trying to bite you it will bite you whether you are speeding away or stopped.
I think it might be good to stop and get OFF one's bike and stand with the bike between you and the dog and command "No! Go Home!" and/or get out your spray at the same time. Most dogs want to CHASE you, that's what excites them. I don't think most of us can outspeed a full-tilt running dog- I sure can't! Take away their ability to chase you and perhaps they will change their mind. I don't think they expect one to stop and become a "normal" disapproving human on two legs.