Did you know that The Rift has 3 paths you can take at the beginning? I never knew that! A bike made my rally T-bone last race, and I entered a very very dark path at the beginning. There's the rig route to the left, then the bike route to the right, and then if you take the bike route and go left immediately after jumping down from the first ledge. There should be a third path. It was so weird haha.
There is a little tunnel in the roof of the bigger tunnel. Go across the bridge(after the canyon section with the water pools, the glitch respawn bridge) instead of the LHS route thru the tunnel(TA route).
As you enter the tunnel, veer up the RHS wall to find the little tunnel. You can get some good air time barrels as you exit higher up.