Minson skatebikes use standard “Old School” skateboard truck hole pattern.
Garel, LeRun and Max skatebikes use a smaller pattern
AXL skatebikes use a third hole pattern
AXL trucks are plastic rather than cast aluminum like the other skatebikes.
This is an AXL skatebike that Jon N from the UK bought. One of the wheels came apart on his first ride. Because the hole pattern is so small he could not fit any of the old skateboard trucks. The axel hanger from an old 70’s Continental skateboard truck fit.
May 19, 2021 update
Jon also found this old Tony Hawk skateboard in second hand shop. The holes are very close and for not much money he got 2 trucks, 4 wheels and 8 bearings.
Most skatebikes use a skateboard truck up front for steering. There is nothing special about the truck except the choice of wheels and bushings. Assuming you are looking at a Minson or a Garel/LeRun bike, you have 30+ year old rubber in the truck. The bushings and pivot bushing will be hard as a rock and the bearings probably need cleaning and greasing.
Jon’s Garel Monocycle, his LeRun Skatebike and Max Skatebikes use an unusual skateboard truck. The mount is much smaller than traditional old and new school skateboard trucks. Minson trucks are Old School – 2 1/2″ X 1 5/8″. LeRun truck holes are 1 5/8″ X 1 1/4″.
Jon took some photos of the original LeRun truck for reference for this site. The bike has not had any work yet. As you can see the bushings in photo one are cracking.
Important: AXL Skatebikes use a similar but different skateboard truck setup.