Transmissions w/ overdrive and lock-up torque converters tend to engage these features at about 40 mph. It's to get you better gas mileage. What it does is slow your motor down for a given speed...which can seem like it is "bogging down". Some drivers disable the overdrive when driving in town by shifting the shift selector to 3 giving you a bit more power, but remember to put it back in "d" when you hit the open road so you can get your best mileage and put less wear on your motor.
"40 mph WOT lag" refers to a transmission pause when shifting at "wide open throttle". Jc
If it has a manual transmission then you can. If it has an automatic transmission you can but not for more than a few miles and don't exceed 40 mph.
If car stalls out when accelerating above 40 MPH, it can possibly be caused by fluid leaks. Another reason can be a defect at the transmission.
Torque converter going bad
tork converter
40 km/h is 24.8548 mph
40 mph = 64.4 kph
Overdrive Solenoid
Average speed is 50 mph [(40+60)/2].
An electric moped will not be able to go 40 MPH.
40 kph = 24.8 mph
Almost exactly 64.37376.