Range Efficiency Under Various Conditions & Cargo

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I just ran the numbers and my efficiency drop was 12%. However - I stuck with the same width tire on that car. 225 is really wide for a Mini (but I bet it's fun!)

I bought the wheels directly from Neuspeed, who also provided tire mounting and ceramic coating options. They only offered 225 width tires and I didn't have the time/energy to buy the wheels then haul them to a local tire shop.

205 width tires will work on these 7.5" wide wheels, but will look a bit "stretched". As I understand it, that should actually improve EV efficiency. However, the visual difference between 205 & 225 on 7.5" wheels is stunning. A friend with 205s on these wheels brought his MINI over to my house to compare.
  • His car looked like WHEEL and tire. :oops:
  • My car looked like WHEEL AND TIRE. :cool:
And, yes, they're quite fun!
 
I bought the wheels directly from Neuspeed, who also provided tire mounting and ceramic coating options. They only offered 225 width tires and I didn't have the time/energy to buy the wheels then haul them to a local tire shop.

205 width tires will work on these 7.5" wide wheels, but will look a bit "stretched". As I understand it, that should actually improve EV efficiency. However, the visual difference between 205 & 225 on 7.5" wheels is stunning. A friend with 205s on these wheels brought his MINI over to my house to compare.
  • His car looked like WHEEL and tire. :oops:
  • My car looked like WHEEL AND TIRE. :cool:
And, yes, they're quite fun!

I bet they look great! I am starting to research my next set of tires. The Pilot Sports would require the 17" wheel, whereas I went for the 16" for better efficiency. That setup still might be a good option for me, especially if you think it is quieter.
 
This weekend, I performed a range test to compare the stock 17"x7" Roulette Spoke wheels with 205/45R17 Hankook Ventus S1 evo 3 tires and aftermarket 17"x7.5" NM Engineering RSe05 wheels with 225/45R17 Michelin Pilot Sport All Season 4 tires. Pictures and discussion on the RSe05 wheels can be found in my Aftermarket Wheels thread.

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Method
I have established my own range testing route, which is 62 miles long per Google Maps and verified by a GPS app. Of those 62 miles:
  • 6.4 miles are on city streets and on/off ramps.
  • 3 miles are at 65mph.
  • 52.6 miles are at 70mph. (The speed limit is actually 75mph for 32 miles, but I maintained 70mph as that's the speed limit on any road trip route I'm likely to take.)
For all highway driving, I used the cruise control set to the speed limit according to GPS speed, rather than the car's speedometer. Likewise, average speed was per GPS. This eliminates speedometer error (due to manufacturer offset and/or different overall tire diameter).

Battery State of Charge was sniffed off the OBDII port via bluetooth adapter and mobile app.

The wheel weights shown in the chart are per documentation on the internet. Wheel + tire weight was measured with my own digital scale.

Both sets of tires were set to factory-recommended pressures: 38psi front, 35psi rear.

Commentary
First, I was surprised that these two sets of wheels & tires had the same net weight. I do expect the smaller-size summer tire to weigh less, but nearly 7lbs less! I cannot find any documented weight for that size of Hankook Ventus S1 evo 3 tire, as it seems to be a rare Euro-only spec. I expected a minor net weight savings with the aftermarket setup (which would improve with summer tires), but alas was mistaken. Maybe the posted weight of the Roulette Spoke wheels is incorrect?

Second, I was surprised that the aftermarket wheels dropped a whopping 20 miles from the range. I remember noting a big improvement in my SE's range when the weather warmed up, but apparently most of that was due to swapping from the aftermarket wheels back to the stock wheels. Since my SE was delivered in late September last year, I only put 115 miles on the stock wheels before swapping to the RSe05s with all-season tires out of necessity.

The additional width of the wheel and tire plus larger offset really fills out the wheel well, pushing the outer face 20.4mm further out than stock. I love the aggressive look, but secretly had second thoughts about having that much poke. (And now maybe third thoughts, given the loss in efficiency.)

This setup provides an even more planted handling feel than the stock setup, with absurdly high corner-holding capability and reduced torque steer. Maximum grin factor. And the Michelins ride much quieter than the Hankooks, which tend to "thrum" on all road surfaces. Most of my driving is shorter trips on city streets, so highway range performance is only an occasional concern as I rarely take trips long enough to push the limit. But losing 20 miles of range in good weather gives me pause--doing a wheel swap would be wise before any planned long-distance driving.

Next Steps
I had planned to get all-seasons for the Roulette Spoke wheels once I wore down the Hankooks sufficiently, but I think I'm going to make that change this fall--likely with Michelin Pilot Sport All Season 4 in 205/45R17. (Then weigh and re-test the range.) Likewise, I had planned to replace the all-seasons on the RSe05 wheels with summer tires at the same time, but instead will resume my search for some light-weight wheels with better proportions/aerodynamics which I find visually pleasing.

I scored a used set of 16" Electric Revolite wheels (Spectre Grey) from eBay shod in lightly-used Hankook Ventus Prime3 tires. I plan to use them for my winter wheels (replacing the tires of course), but will perform a range test with them as-is first. I will update my chart and post an update here once that's done. I expect efficiency to be a bit better than the Roulettes.
If I had to guess your losses are probably 70% rolling resistance, 25% drag due to wider wheels/tires, 5% from the wheels themselves.
 
Tire rack used to include rolling resistance in their tire tests but have not as of late. I’ve used the Mich Pilot Sport A/S 3+ on my 3 series and can confirm a drop in mpg. It makes sense that they are sticky given that aggressive tread pattern they need to make up for to give them decent winter traction. Probably safe to assume for the new A/S 4 as well.



Sent from my iPhone using Inside EVs
 
I have some new data to add to my previous range tests. This time, I have tested:
  • Stock 17"x7" Roulette Spoke wheels with 12.5mm spacers, shod with 205/45R17 Michelin Pilot Sport All Season 4 tires.
  • Stock 16"x6.5" Electric Revolite spoke wheels with OEM 195/55R16 Hankook Ventus Prime 3 tires.
index.php


Method
I used the same range testing route as prior tests, which is 62 miles long per Google Maps and verified by a GPS app. Of those 62 miles:
  • 6.4 miles are on city streets and on/off ramps.
  • 3 miles are at 65mph.
  • 52.6 miles are at 70mph. (The speed limit is actually 75mph for 32 miles, but I maintained 70mph as that's the speed limit on any road trip route I'm likely to take.)
For all highway driving, I used the cruise control set to the speed limit according to GPS speed, rather than the car's speedometer. Likewise, average speed was per GPS. This eliminates speedometer error (due to manufacturer offset and/or different overall tire diameter).

Battery State of Charge was sniffed off the OBDII port via bluetooth adapter and mobile app.

The wheel weights shown in the chart are per documentation on the internet. Wheel + tire weight was measured with my own digital scale.

Tires were set to factory-recommended pressures:
  • 17" = 38psi front, 35psi rear.
  • 16" = 35psi front, 32psi rear.
Commentary
Performance of the Michelin Pilot Sport All Season 4 tires in the stock size is on-par with what I experienced using the larger size on the NM Engineering RSe05 wheels. Tire noise is significantly lower than the stock Hankooks. They still thrum, but at a lower tone and much lower volume--barely noticeable. Likewise, dry traction is excellent though ultimate cornering grip is slightly reduced compared to the much wider 225 Michelins on the RSe05 wheels. The higher rolling resistance is also apparent, at a cost of 0.53 mi/kWh or ~15 miles when driving at interstate speeds. Dang.

As expected, the lighter weight and more aerodynamic Electric Revolite wheels with low rolling resistance Hankooks have shown the best consumption values to date. (On one particularly efficient trip using slower city streets, I managed to get 5.9 mi/kWh!). I was pleasantly surprised by the handling capability of these Hankooks with taller sidewalls. The additional sidewall flex reduces turning response just a bit, but not enough to actually put a damper on the SE's handling prowess. European labels show the 195/55R16 Hankook Ventus Prime 3 tires are 1dB quieter than the 205/45R17 Hankook Ventus S1 evo 3, and that's noteworthy because the decibel scale is logarithmic. These tires thrum at the same tone as their 17" cousins, but the volume of that sound is much lower to my ears so not nearly as noticeable.

I haven't been able to find any European labels for Michelin Pilot Sport A/S 4 tires, so can't compare any rated rolling resistance values for them. However, European labels rate the rolling resistance for both the 195/55R16 Hankook Ventus Prime 3 and 205/45R17 Hankook Ventus S1 evo 3 as 'A', the most efficient. Browsing other makes and models of tires shows that the performance characteristics--including rolling resistance--for these Hankooks make them uniquely qualified for the SE (in the summer). I see why MINI selected them.
 
I need a second set of wheels for snow tires but I'm having such a hard time deciding on what direction to go... I had planned to use my 16" victory spokes for winter and upgrade the summer set to something a bit more aggressive but can't find any good options and am torn between maintaining efficiency and something that improves handling.

I had almost convinced myself to just go 17"x7.5 (OZ Superturismo LM) but that's a pretty significant difference between even the stock 16 and stock 17... I'd love to stay with 16" but all the wheel options seem to be 17"+ and 7.5" or 8" wide.

I really want something like the wheels from the Porsche Mission R concept or the OZ Superturismo AERO but can't find anything under 18".
live-photos-of-porsche-mission-r-from-iaa-2021.webp


01_SuperturismoAeroPost_StarGraphite.webp
 
I understand your frustration, @Carsten Haase, as I am also trying to find a different set of wheels for summer that are the right size, with an appropriate offset, lightweight, aerodynamically reasonable, and aesthetically pleasing to me. :confused:
 
Battery State of Charge was sniffed off the OBDII port via bluetooth adapter and mobile app.

@MichaelC which app are you using? I've tried to get Torque to work but it refuses to connect to the MINIs ECU. I also tried the $40 BimmerLink (same dev as BimmerCode) but it doesn't support reading sensors on EVs.

The only one I've found for Android is an early access app called electrified designed for the i3 but it doesn't support any data logging, just display.
 
@Carsten Haase I have an iPhone, so use an app called "mi3". It is also display-only, so I just take screen shots as needed (then record a voice memo to give me context later).
Another app for iOS and Android has data-logging and csv export: Car Scanner ELM OBD2.
There's even gps logging and trip visualisation on Google maps.

Mini Cooper SE profile should be manually selected at setup.
 
I am so glad ideal driving weather has returned! My wife and I did a 27 mile drive this evening. I'm about to pass 7,500 miles, so I wanted to do another comparison of range with and without my crossbars on the roof.

I will repeat tonight's route tomorrow once I put the crossbars back on. But, I had excellent range today with bare roof! (No interstate)

Route: 27.6 miles
Speed: 45 to 60 mph
Power: Kept under 50%
Driving mode: Mid
A/C: On and set to 68F
Traffic: Almost zero
Temp: 75.2F
Wind: 3.7 S
Humidity: 51%
Start-Batt: 100%
End-Batt: 82%
Mi/kWh: 5.31
GOM range left: 83 miles
Calculated range left: 125.84 miles
Total range: 153.44
 
It's funny, I expected to be scrutinizing the range/efficiency every day I drove this car. I have a short commute each day (20 miles round trip), charge every 3-4 days and haven't given it a second thought. I coded to be in Sport as default, and couldn't imagine staying under 50% power for ANY drive... I'm going to my first NorCalMINI fun run in May, I may actually put it in Green to get there, though I'm still well within my projected range for the trip. I'm very curious how this compares to BMW CCA fun runs, which are *VERY* spirited. Regardless, looking forward to the new community!
 
I am so glad ideal driving weather has returned! My wife and I did a 27 mile drive this evening. I'm about to pass 7,500 miles, so I wanted to do another comparison of range with and without my crossbars on the roof.

I will repeat tonight's route tomorrow once I put the crossbars back on. But, I had excellent range today with bare roof! (No interstate)

Route: 27.6 miles
Speed: 45 to 60 mph
Power: Kept under 50%
Driving mode: Mid
A/C: On and set to 68F
Traffic: Almost zero
Temp: 75.2F
Wind: 3.7 S
Humidity: 51%
Start-Batt: 100%
End-Batt: 82%
Mi/kWh: 5.31
GOM range left: 83 miles
Calculated range left: 125.84 miles
Total range: 153.44


Certainly weather makes significant difference… I was glad to see improved efficiency on a 62F day…

2973bced3e9aaed6b99e15d319d4fc0d.jpg
 
Crossbar efficiency result:

The conditions for my drive with the crossbars yesterday were almost identical to my last post. For sub-highway speed travel, the crossbars do make a difference, but not as big as I expected. I will test with my bike on the roof at some point. I did a bike test last year, but not with this particular test loop. This route has really low traffic and allows for consistent driving conditions.

Final results: Approx average speed for both trips: 48 mph
Crossbars? - Miles - Battery-Used - mi/kWh - Total Calc Range
No - - - - - - - 27.6 - - 18% - - - - - - - 5.31 - - - - - 153.33 miles
Yes - - - - - - - 27.9 - - 19% - - - - - - - 5.08 - - - - - 146.84 miles
 
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FINALLY drove Uncle Larry more than 30 miles in one trip yesterday. Started at 100%, went from San Ramon over to Hayward, picked up 3 regular-sized friends, then to South San Jose to see Hasan Minaj. Then back the same route. I put it in Green (for the first time since I bought it) on the way down, then left it in Sport all the way back. Round trip of 99 miles, got back home with 28% SOC. AC was on the whole time, and otherwise ideal driving conditions, about 75% highway though plenty of traffic to keep me <60mph. I couldn't resist getting over 50% power many times, but not as much as usual. So that appears to put my range at 137mi, totally happy with that.

Charged overnight to 100%, then today went on a NorCal MINI fun run through the Oakland hills (moderately spirited) AC going the whole time, total RT from home was 62mi, returned home with 54% SOC. So, about 135mi range. I will probably never use Green again!!! :D No doubt having 4 full-size adults vs. 1.5 adults (bribed my teenager to come on the fun run) makes a difference, but not worried about that.

Good to FINALLY see other SE's on the road (2 guys from here), hope to see more again someday. It may have to wait until another local fun run?
 
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