I have long commute to work that is mostly highway and I have noticed a change in my gas mileage. I remember the gas light coming on around 140miles or so on the trip meter. Now its coming on just after 100miles.

Around 13k on the odometer, I added the race ecm, secondary muffler removed, tank vent rerouted to atmosphere, de-noided, 44t rear sprocket. Now I'm up to 15k on the odometer.

I was riding stock before these upgrades and covid changed my commute since there are now less people on the road. Could it just be that I'm heavier on the throttle now with all this open road and thats dropping my gas mileage? Anyone have any similar mpg drop?