After riding the traverse (with whoops) and leaving Top of the World
at the Hwy 86 corner, or climbing Hwy 86 (mountain access or FSR), look for the sign on the downhill side of the rooty knoll. This is the newer entrance to Khyber.
This singletrack generally flows well and perfectly suits a 4-6" bike; It's not really designed for DH bikes. Be ready for some steep chutes and rooty corners with a few cheeky short climbs thrown in.