Spare tire solution

[jaguar36]

I had an evaluation set of runflats on my S85 and they increased th Wh/mi by 30 to 60 on my regular commute. 15% to 25%. The reason ICE cars seem less is that ICE drivers don't keep records.

Where they with the same tire compound? The tire compound could have a significant difference in energy usage, and as Mknox mentioned, there aren't many low rolling resistance run flats (the Primacy 3ZP is the only one I know of) even with tires rated for 'low rolling resistance' there can be a significant difference in energy usage.


Some ICE drivers keep very meticulous records. On my BMW, when I switched from run flat Michelin PS2 to regular Super Sports, which is a similar compound, my mileage actually increased by .1 mpg. That's probably in the noise, but could be because the Super Sports are slightly stickier.

 

[mknox]

Some ICE drivers keep very meticulous records.

I always did as well. If I go back over my logs, you can easily see when I did my summer/winter and winter/summer tire changeovers. I'd lose between 2-5 MPG on the winters right at the time of switchover. Helps that I drive a very predictable route on my +/- 90 mile round-trip commute.