Derail Valley is a cool solo adventure where you take on jobs as a train engineer, its a one man show, you load cars, hitch them to your engine and transport them to other towns on the “worst” rails ever 
hence Derail Valley.
Anyhow. I have the 5K+.
When standing still in the game I have no problems but when I teleport around or get in the engine and drive around is when it stutters, it happens as the world is moving, the screen freezes for a half second, sometimes the “Derail Valley” Steam logo appears and then quickly disappears and everything goes back to normal for 20 or 30 seconds or so then it happens again??
Pitool is set to 1.0, Steam is set to automatic and running at 58%. PP off, Pimax Home is off, fpsVR tool shows my GPU doesnt get above 65%/70 degrees, CPU averages 45% and average FPS is usually always a good 70 FPS.
Any suggestions? THX! 
PC specs:
CPU I7-4790K 4G
GPU 1080ti
16G DDR3
Pitool .91
Windows 10 Home
vive controllers and light houses