Wheel Option questions

[I33t]

Hi, can anyone shine some light on the wheel options on offer?

I don't think I'm up for the 20" but I'm not really taken with the other options.

I think this is my preference:

But what does 'EffDyn' mean? The other options say 'mixed tyres' Does that mean 'mixed tyres' comes with different sizes front and rear? Are any of these runflats? (no thanks)

Appreciate any explanation...

 

[Plug]

The sizes for the Wheel & tyres are shown on the UK site (there's a little drop down to flip between the two models). You can see that for the REx there are different sized tyres front and rear. They aren't runflats.

"EffDyn" just stands for Efficient Dynamics which is marketing speak for a BMW design 'philosophy' which they have been running for years specifically aimed at reducing fuel consumption & emissions. The i3 tyres are narrow low rolling resistance designs and all four wheel designs are aerodynamically flat shapes to reduce drag. EffDyn !!

There are only the 4 different wheel designs to choose from (shown on the configurator).

I actually changed my mind on the standard wheels (shown in your pic). When the test cars were running around before the launch these wheels looked pretty bad but since then they have been subtly changed to add more depth/shape to them and when I saw them for the first time on my test drive I actually changed my order to spec them.

Development car

Best pic I could find showing the tweaked design (ignore the snow chains :lol: )

They're still not exactly the prettiest wheels in the world but the i3 isn't the prettiest car in the world either so it's ok I felt quite frugal for a while (had originally spec'd the 20") but then went and persuaded myself to use the money saved on the Driving Assistant Pack instead :roll:

 

[I33t]

The sizes for the Wheel & tyres are shown on the UK site (there's a little drop down to flip between the two models). You can see that for the REx there are different sized tyres front and rear. They aren't runflats.

Aha. Got it, thanks. So the extra weight of the REX unit caused an upgrade on the wheel and tyre width at the rear!

I think my original selection stands. thanks for the up to date pic with the chains!

Next question. Are all these wheels comparable weight in the same sizes?

 

[Plug]

I've never seen the weights for the wheels. I'm borrowing an owner's manual later this week so I'll let you know if it's mentioned in there.

 

[Jkoeller]

I was concerned with the different tire sizes as well. How are tire rotations done when the front tires are a different size than the back? Will this decrease the expected life of the tires?

 

[Jkoeller]

If the different tire sizes were isolated to the REx option, I wouldn't be concerned, but looking at the ordering guide it appears that any BEV configuration using anything but the base model wheels will result in differing front/back tires. (footnote-1 is just a warning about the increased chance of damage to low-profile tires).

 

[I33t]

Thanks for the further info John.

So the plot thickens!

Tyre rotation is an issue with different sizes front and back. The only opportunity is to swap across the vehicle but that has limited benefit and not possible with directional tyres unless the tyre is removed and flipped on the rim. In reality, with rear drive and the i3's weight, the fronts should outlast the rears by a fair margin but tyre life should be quite good anyway.

Unless there is a great handling benefit, sounds like the standard wheels will be the most convenient option. I've run the sizes through an online contact patch calculator, (assuming specs for speed rating and load index, 2.5bar is approx 36psi) There is a patch benefit, not sure how that would relate to handling on the car though.