That is exactly what I used to do on my earlier bikes, used the trip odometer to estimate how much fuel I had left.
That's what I'm still doing in 2020 on my car. Standard fuel indicator works a charm, but the one for the LPG tank has always been totally shot, so for me it's roughly 350-380 km if mostly city, 480-500 km if mostly outside. At least I can afford missing the estimate and simply petrol my way to a LPG station.
Also, cheers askavir!
