Adding onto Pookemon - I had to add a Torque curve. I spent a day and a half debugging, re-importing, re-working physics bodies, double checking Simulate Physics was checked on for the skeletal physics mesh, trying everything to get the vehicle moving but only the torque curve got things working. If you think you’ve done everything right and it’s still not moving, definitely check/add the torque curve.
Also like Pookemon I am trying to figure out why reverse doesn’t work. It seems to also have to do with the torque curve, because I can only reverse when I give that curve negative values. At which point, I can no longer move forward. I feel like I’m missing something obvious here. The Input axes are clearly getting read correctly, print string shows 1 and -1 for forward/back. It’s something in the vehicle.