Not sure on this one, but just to let you know you really should have your doodle run with you (jogging or next to a bike) until they are 18 months old... while they are younger their joints are growing very fast and lots of running or jumping can hurt their joints and make them more prone to things like hip displasia. Just FYI!
Kelly is absolutely right! You should wait until 18 months for your dog's safety. But, after that, there is a great site about biking with your dog. It is written by a woman who owns dobermans, but it applies to any dog. She uses a Springer, available at lots of online dog supply stores. Here's the link: http://homepages.udayton.edu/~merensjp/ ... index.html I hope this helps!