Notes on the CG Guide Adapters: The ‘Standard’ size fits the BMW and Ford-GT. The large size can fit if sanded down. I recommend sanding down the adapter, not enlarging the chassis hole, (b/c a replacement adapter is easier to get than a new chassis). Reference Ary’s video.
Warning: It does Not take very much sanding to make the large adapter fit. Be sure it slides in easy, without warping from forcing it. Also: These are 3D printed items and the track facing part of the adapter has a rough finish that needs careful sanding to smooth it.
Removing Rear Magnet: The magnet behind the motor is held in with a U-shaped clip. Try and pry it out with a small flat-blade screwdriver. If it sticks, you can very very very carefully pop out it out from the bottom of the chassis by placing the screwdriver on one side of the exposed part of the magnet and popping it with your palm. Carefully!
"... get on your bad motor scooter and ride!"
Sammy with Montrose