so I believe than the tires, pressures and weight of each tires has the biggest effect on the range.
here are some things I have learned over the 50k km I have in my 2016 twizy.
my rear tires only last 23k km. I drive mostly on the open road at an average of 40 km/h and I drive fast, that is why my tires last so little. I imagine in slower city driving they can last longer. I do take them to the limit, so I only change them when there is no more tread left, basically making them slicks (-:
the continental rear tires 145-80-13 weight a little over 5 kilos. I am trying the kenda ones right now. (third set now) they are heavier, they weight 6 kilos. I have noticed a lower range with these, maybe a reduction of 2 % when compared to the conti ones. I am interested to see if these will last longer, I am only 2k km so far on these, I have noticed that the car is less stable, I believe it is because the kenda ones have a softer construction and the tires flex more under hard cornering
I pump the tire to the max psi , I used to have them at 32 psi in the first few month, but I have noticed an increase in range of about 3% when the psi is at 44. I recommend this, it has a harsh ride but it compensates with the extra range
I had tried to fit the smaller front tires on the rear trying to figure out if the smaller contact area would provide more range and be more efficient, but I got the opposite. the smaller contact area of the front tires, do provide a faster acceleration, but the less circumference, requires more turns to cover the same distance, so inevitably the range is decreased. I imagine if you do short urban routes, the smaller tires provide a faster acceleration. the car also sits lower, so it was not a good idea.
so that is basically some of my experiments and try outs on tires. if anybody has any other ideas, or insight, I would much appreciate it
carlos from colombia