2006 Yamaha APEX RTX (w/reverse) Service and Repair Manual
The reverse-equipped RTX shares its factory manual with the rest of the early Apex family. LIT-12618-RX-01 covers the 2006 and 2007 seasons, including the standard Apex and the Attak, and the RTX here is model code RX10RTRL.
On a sled with reverse the drive and power train sections are the ones to read closely, and the manual treats them as factory procedure: removal sequences, inspection measurements with limits, adjustment ranges and torque figures.
The rest of the book is equally complete. Periodic maintenance, engine and fuel system work, cooling, chassis and suspension, brakes and steering, and an electrical chapter with diagnosis routines and wiring diagrams for the machines listed. Where a specification differs between the variants or the two years, the table names the code it belongs to.