I started biking in because I don't have a 4x4 anymore. It gets me further in much faster than walking. I've found that the bike noise doesn't spook game like walking does. (Wet, dewy, grassy country.) Last season, I went around corners and ran into (within 30 feet) skunks, raccoons, deer, and several hawks. Really surprised me. Evidently the constant sound of a wheel on the ground doesn't alert the game where I hunt like footsteps do.
I've got a little trailer that I use in the event of hauling out any massive game. Of course, I have yet to use it...
I use a sort of a fanny pack that has two quick-release straps that fit my bow perfectly, but that's to carry the bow horizontal and on my back. I also bought a backpack this spring that has lots of external lash points, and I have some homemade straps that hold my bow -- in this case, vertical. I've also installed some ATV gun holders on the bike handlebars now, and it works great... if the trail is wide enough to accomodate the bow horizontally.