If you want to get to that level of discernment, the only way forward is to ride bikes with the different setup on an identical course, and then ride them many times, keeping note of the ranges achieved. The confounding variables would be, temperature, wind speeds, terrain, and road quality. You probably ought also to use the same tyres and at the same pressures. If you REALLY wanted to do this, I would say you should ride the bikes around a velodrome of some sort, to get rid of terrain differences, wind, road surface, and temperature variations Better still, just forget about it and ride with a nice big battery, and carry a couple of pies to make sure that if the battery lets you down, you have enough energy to get home. It used to be so simple when I was young, and just rode my bike, and carried a couple of Mars Bars in case I got worn out. I remember taking my eldest son on a long ride when he was eight. He is 46 now and a lot heavier than back then. We rode from Newcastle to Richmond and then cut off to go to a youth hostel at a place called Ellingstring. Coming up a hill to Richmond, he started crying and saying he had no more energy, so I just chucked him a packet of chocolate digestives. He sat on the verge, bubbling and ate two thirds of the packet, and then as if by magic, he got up and started off again and rode the rest of the way without complaint. We rode 65 miles and he broke down at a bit over 50 miles. Surprisingly - he still speaks to me. Social services were not involved.