Plus, since they get totally machined on the CNC Router, the holes, drop throughs and shapes are perfectly accurate, no «crabbing» boards goin’ down the street. These trucks are useful for making sliding easier, and also for many beginners who are struggling with speed wobble. Pumping Pumping a skateboard is a technique used and perfected in slalom skateboarding. It is a technique used to maintain speed without the rider taking his or her feet off of the skateboard. Carbon fiber and fiberglass are used to strengthen or completely replace wood in decks because of their better strength to weight ratios.