Finally, I found something big! The rubber wheels were installed right. I flipped the left and right rubber wheel，which are the driving wheels, then, you know what? The robot is no more going left, but veering rightA! So the rubber wheels are not built the same!
Great to hear! Did you find 2 sets of rubber wheels that roll the same (or are more center aligned)?
Yay, happy to hear you figured it out.
Yes， I tried some and found the same wheels.