Welcome Kymco Owners!
the gas bars go down slow for 200 Km. after that it goes fast, 300 Km. to 340 Km. empty, the most at 80 Kmph I got 410 Km. riding on country roads, no traffic, on my downtown 300i ,
If you look at the shape of the gas tank, you'll see it's pretty irregular:https://www.oemmotorparts.com/fiche-l/KYMCO_Downtown%20300%20i%20ABS_Fuel%20%20tank.pngMost likely there's no way for that float on the sender to actually reach the very top. So first the fuel level needs to go down to a point where the sender will even start to register that fuel was used.Then, the tank is wider at the top than at the base. So unless the sender goes through some kind of processing (not sure), you'll see an acceleration in how quickly the bars fall relative to the actual amount of fuel used.So all of us will have this unpredictable mark because of the gas tank being deformed ??
It's never accurate. It's better to rely on distance travelled.
Out of character in my experience. De dee said something like it does not move at all then moves fast! The two DT's I have had both would go about 85 miles before the first of the 5 bars disappeared then would go about 115 miles to leave just one bar showing. The bike would travel generally about 230 miles on a full tank before it was very, very close to flame-out. This one in Brazil goes down two bars in 10 kilometers! That tells me the sender is bad. Float, pump and arm are OK but the variable resistor of the sensor is faulty. Keep the pump but change the resistor. Use parts out of a salvage yard because the thing comes as an expensive assembly.
... that's a good catch, paying attention to the distance traveled.