I guess that that is the most likely cause. I hope you find the problem.
Hey I noticed that on my 2018 750 there is no line? Did you figure that out?You know what's funny about your post is that today I was checking on my 17 model for the tps setting and on the dash is displayed the coo but no line apparently the 17 18 models don't have the adjustment and I was just checking things.
So I'm there twisting the throttle back and forth thinking maybe something is out of whack as there is no little line to speak of so about 1/2 hour later I go for a ride and start thinking I must be getting used to the twitchy throttle but then I see your post it's got me �� Thinking.