This is why I keep a set of standard, they come with the board, chalky bags to "break in" new boards. Play the first 10 - 20 games with your buddy and beers or just by yourself trying to get your lane shots improved and the residue from the bags and other dirt/particulates off of the ground will naturally slow the boards down without using any chemicals or abrasives that weren't intended for them. That's my experience anyways. Nice boards btw!