Best Nordic winter tires / grip issues

[racc]

I've been quite happy with my 2020 120Ah i3 BEV, but recently I've too often ran into situations on relatively low highway speeds (around 80km/h -- 50mph) that rear loses grip even on most gentle acceleration or careful regen/braking I'm able to do. Road has had no visible ice, it is just slippery (-2C, no salt). The result is rear loosing grip, and desperate wiggling and squirming when ESP tries to restore stability. Other drivers seem to be just fine.

Tires are Continental VikingContact 7. I'd guess the set has been driven under 10000 km and that were likely manufactured in 2019. I thought these were supposed to be pretty much best possible winter tires available for i3.

I'm starting to seriously loose my confidence to the car. Now even slightly curving road makes me horrified in these near-zero (Celsius) degree conditions, as fear of suddenly loosing lateral grip is always there. I'm feeling like the safe speed limit for the car in winter is around 50 km/h. I'm happy to drive slow, but it is not exactly safe when everyone else is going 80-100 km/h...

Any thoughts, like is this normal i3 behavior? Could a 3-year old tire set be so significantly degraded? Could new Nokian R5 give significantly better grip? Is there any other options? Should I just change the car to something else?

 

[agzand]

Eco Pro might help with acceleration part. As for regen, I think the only option is to control it with your foot. Don't let the accelerator go suddenly.

 

[racc]

Thanks for the reminder! Yeah, I've indeed used Eco Pro sometime. It would had been good idea now too.

However, I'm able to fail also with Eco pro... Just after buying the car (on way home from the dealer) I got into the most dangerous event I've had. Admittedly weather was horrible. It was motorway, storm wind, snow & slippery conditions. The car was new to me, and I was struggling just to accelerate to a decent speed. I knew Eco Pro would help controlling the acceleration... just I forgot I had already activated it! So i3 went into Eco Pro plus with speed limiter configured.. Regen hit violently when car started strongly slowing down, rear lost grip even worse than in my acceleration attempts, ... you know how it feels (actually, i hope you don't...) :shock: After I was driving straight again, I drove 60 km/h or less, hoping nobody will rear-end me, and took the first exit and took an extra hour to drive home smaller roads.

Slowing down gently enough still feels sometimes challenging even though I've had the i3 over an year already. This non-adjustable regen is a real PITA in winter. I've some aftermarket pedal tuning boxes , but idea of adding such electronics to such critical place isn't exactly intriguing.

 

[agzand]

I think traction control is not working properly on your car. It should limit wheel spin and fishtailing due to regen. The way you describe it I get the feeling that it is not working. If you are running summer tires then yes, there is no amount of traction control that can overcome physics, but with winter tires it should drive solidly even in snow and ice.

 

[racc]

Thanks for your thoughts!
I called to my local BMW service, but they just told never hearing about such issues before, and that there was no any recalls or updates related to such issue they were aware of. :|

I've been reading forum posts quite extensively. It feels like there is two different cars out there: some seem to be describing exactly situations I've ran into. Some, perhaps fewer, comment their i3 behaves just like any other car.

I guess there is few alternatives here:
1. There really is something broken or different in part of i3 cars.
2. Some commentators have avoided getting into conditions that triggers this behavior.
3. Some people are actually able to ignore the horrifying fish tailing and ESP struggling to stabilize :shock:
4. Could it have something to do with loading of the car? I realized that my worst experience happened when I had i3 summer wheel set loaded to the back of the car. Next times there was wife and baby on the backseat, and also some stuff in the trunk. Could be just coincidental, of course... According to specs at least 120Ah BEV is slightly rear-balanced already.

 

[cdnji]

I live in BC Canada. In general, winters here are mild. But on occasion, we get some surprises.

I have a 2017 i3Rex with Nokian Hakkapelitta tyres. The Rex generator puts additional weight at the back which helps with handling. Because it's winter, I also carry around some winter gear that adds some more weight - bag of road salt, a pair of Konig K-Summit chains, etc).

You're right, even with the loading, using EcoPro, I tend to avoid getting into conditions that trigger fishtailing. I ease off the accelerator early; keep my following distance to at least 6 seconds; I don't exceed 80km and even go as low as the minimum 60km in the highway depending on conditions. It's the same thing I learned to do even when I had an ICE car. I also tend to drive slower when the car is loaded.

Check the tread depth of your tyres. Mine is still at 6mm. Minimum here is 3.5mm. Maybe there's an opportunity to rotate between the front and rear tyres - if your winter set has the same size across all 4.