About the Physics of Vehicle

Hi,guys,I was made a Motorbike by WheelVehicle Blueprint.
I think that there is a playercharacter should be attached to the Motor after interaction ,but they once
be attached,then the motor will fly crazy. And they both work well single,I see there could be something wrong with the setup of physic,but what and where should I do to fix that?

I think you should turn off the collision of the player character when the character is attached to the motorcycle