So, I changed over to my winter tires this weekend and re-measured the regen force, and even on my AWD I do see a difference in the regen at high speed, and then at low speeds it seems 'normal' as others have noted. Below is a plot with some markups of the comparisons, but to make sure I'm clear on the configs:
summer plot:
OEM 18" tires
After market rims (same weight as aero's ~ 20.5 lbs)
After market TPMS
Starting speed 100 km/h coming off the highway at winston churchill in mississauga
winter plot:
continental SI winter 18" tires
OEM aero rims with no aero hub caps
OEM TPMS
Starting speed 100 km/h coming off the highway at winston churchill in mississauga
There are some fluctuations up and down because I couldn't just take the car to a full stop since there were cars behind me. On my test this morning (winter plot) I did bring the car down to ~ 20km/h and at the trailing end of the plot you can see when the 2nd stage of regen kicked in at ~ 30 km/h (blue arrow).
This thread has a lot of people reporting the same thing, but I thought having a visual comparison that is somewhat apples to apples would help put things in context.
Also, since I have an AWD it would be interesting to see a similar comparison on a RWD car since some have commented this issue isn't on AWD (or likely less affected). I wouldn't say I have zero regen at high speeds, but it does seem softer. Also I see the same thing others have said where the regen green bar seems to 'flutter' a bit at higher speeds.
View attachment 352295
So, to add some more comments to the above plot:
Summer (blue) plot:
Initially I slowed down from ~ 100 km/h to 50, then had to speed up a bit (where the force increases at about 18s on the y-axis). The second major dip at around 30 sec brought the car to an almost complete stop, and you can see that the force maxed out at ~ 0.25g.
Winter (orange) plot:
The initial 'drop' in force was about 1/2 of the drop from before the change to winter tires, and interestingly the force slowly increases at about the same slope as the summer plot. But then you see at around 20 seconds I hit 30 km/h and the increased regen kicked in (blue arrow). I couldn't let the car come to a full stop there unfortunately because I was well short of the stoplight so had to give it some gas to keep moving forward. If I had stayed off the accelerator though I expect the force would have reached ~ 0.25g and stabilized there. Ignore the rest of the plot because I had to speed up, and the huge dip at 40 seconds was me using brakes to come to a stop.
