The Diamond non-boost fork travel can be configured to 140mm, 150mm and 160mm. Travel adjustment is done by changing the spacers inside the air cartridge. This task should be performed by an Authorized DVO Suspension service center or a qualified suspension mechanic. Below is a video and a step by step PDF guide that show you how to perform the travel adjust.
WARNING! PLEASE MAKE SURE THAT YOU RELEASE ALL THE AIR OUT OF THE AIR CARTRIDGE BEFORE PERFORMING THIS TASK. SERIOUS INJURY MAY OCCUR IF YOU DO NOT REMOVE ALL AIR FIRST. YOU HAVE BEEN WARNED!
Click here for PDF Diamond Non-Boost Travel Change Guide