Whether it's the trucks axles, the chainring, or the Kingpin, we advise you to check regularly (not to say at each session), the tightening of the screws.
Concerning the screws that fix the trucks on the chainring, they have an annoying tendency to unscrew with the vibrations, in spite of the plastic brakes that are in the nuts. If these screws loosen, the truck becomes loose, and we increase the risk of breaking the base, the screws, and the risk of falling.
As for the nuts of the axles of trucks, it is a question of checking that the play that we leave to the wheel to roll correctly does not increase too much, at the risk of increasing the risk of breaking the bearings.
Finally, check the kingpins, especially to avoid losing the nut in the middle of a session, which is quite dangerous.