Bike with rolling wheels

Hello everyone!

I am trying to set up a little Bike that can roll around. I have a simple model that consists of a main body, a steering part, front and back wheel. Now I have all on the same level, parented to an empty object.

I want to be able to get the bike rolling by rotating the wheels, and if it rolls a hill downwards, it shall 'stick' to the ground, kind of like IK but for a bike.

Now i figured to do it like this : Add a rigidbody to the body, and two wheels. Add a collider to those three. Add a hinge Joint to both wheels and add the main body as connected rigidbody.

Now in my imagination this should work, and the wheels should be 'falling' to the ground, taking the body with it to get the real feel.

But all it does is spin the wheels crazily around. I tried to fix axes in the rigidbody but without any success... Anyone can help pls ?