NON OEM wheels & tires (wider)

[jadnashuanh]

I wonder how many of those tires available in Germany have the low rolling resistance of the Bridgestone that was purpose built for the i3.

The only way to get a taller sidewall would be to use a smaller diameter wheel if you want to retain the overall diameter that would keep the gearing, speedometer, and odometer accurate. Don't know if there's enough rotor and caliper clearance for that. That would also likely increase the contact patch and therefore rolling resistance.

 

[joeguzman10]

I wouldn't care about efficiency if the tires have, longer life, less expensive, and possibly safer.
Someone mentioned using size: 215 50r18 which widely available.

My question is will standard rims work?

 

[jadnashuanh]

If I ran the numbers properly, that wheel/tire combination would be about 1.1" smaller in diameter, which is about 4% off of the stock combination in circumference...that would mean your speedometer and odometer would be off by 4% on top of the speedometer's approximately 2mph buffer it builds in. You'd be putting 4% more revs on the motor as well.

 

[benrk]

The rims actually are not the problem, 3 piece rims can be configured to diameter, width & offset as desired, it’s just expensive, but not a technical hurdle. The true problem is indeed the tire size. Large diameter tires usually are fairly wide, providing a much larger contact patch than the i3 has from factory, which greatly increases rolling resistance and thus eats into the already rather low range of at least early model i3s. Besides, there simply is no space in the wheel housings for wider tires & you’d have to run pretty wide fender flares or custom build something reminiscent of an ‘80s groub B race car or Rieger wide body kit, I personally don’t consider that very desirable. If you don’t want to run something ridiculously wide, you’ll probably have to shrink overall diameter/circumference to come down to something more reasonable like 195 or 205. You’d probably still be looking at a rare tuner size or steering tire size for RWD sportscars, which will just as much have very limited tire choices & you’ll still need fender flares & lose ground clearance while increasing the arch gap. The best thing we can all do is communicate with big tire dealers like Tirerack or Discount Tire in the US & voice our desire for more tire choices, so maybe they’ll start bringing some of the European options in and talk to the manufacturers to offer more tires.

 

[alohart]

Large diameter tires usually are fairly wide, providing a much larger contact patch than the i3 has from factory, which greatly increases rolling resistance and thus eats into the already rather low range of at least early model i3s.

This had been my belief until I was shown the error in my ways. The size of a tire has no bearing on the area of its contact patch, only on the shape of the contact patch. The contact patch area is equal to the weight the tire is supporting divided by the inflation pressure. E.g., in an approximation for an i3 rear tire, area = 750 lb. / 41 lb./sq. in. = 18.3 sq. in.

If a wider tire were installed on an i3 and inflated to the same pressure as the original tire, its contact patch area would be identical but would be wider and shorter (in the rolling direction). The rolling resistance of a wider tire might be less because the sidewall would not deflect as much to form the contact area needed to support the weight. Probably most important, if the wider tire were not be designed as a low rolling resistance tire, the wider tire would have greater rolling resistance than the original low rolling resistance tire. Regardless, the aerodynamic drag of a wider tire would be greater.

 

[benrk]

Large diameter tires usually are fairly wide, providing a much larger contact patch than the i3 has from factory, which greatly increases rolling resistance and thus eats into the already rather low range of at least early model i3s.

This had been my belief until I was shown the error in my ways. The size of a tire has no bearing on the area of its contact patch, only on the shape of the contact patch. The contact patch area is equal to the weight the tire is supporting divided by the inflation pressure. E.g., in an approximation for an i3 rear tire, area = 750 lb. / 41 lb./sq. in. = 18.3 sq. in.

If a wider tire were installed on an i3 and inflated to the same pressure as the original tire, its contact patch area would be identical but would be wider and shorter (in the rolling direction). The rolling resistance of a wider tire might be less because the sidewall would not deflect as much to form the contact area needed to support the weight. Probably most important, if the wider tire were not be designed as a low rolling resistance tire, the wider tire would have greater rolling resistance than the original low rolling resistance tire. Regardless, the aerodynamic drag of a wider tire would be greater.

Now that is really interesting, I never thought of it, but it makes perfect sense!

So what does that mean? You’d have a large diameter tire with a wide contact patch & a weight rating that’s likely a fair bit higher than what the i3 needs. So that gives you a very wide and very short contact patch, probably shorter than the tread pattern was designed for. Yes, it will increase wind resistance, which actually is of lesser importance for a city car that’s primarily racing from stop light to stop light. Hydroplaning risk also is greater, but once again not really relevant at city speeds. Anything else?

 

[alohart]

Now that is really interesting, I never thought of it, but it makes perfect sense!

That was exactly my initial reaction to this revelation.

So what does that mean?

We know that drag racers discovered that a wider tire provides better drag racing traction even thought its contact area is no greater. Maybe for drag racing, spreading the acceleration force and resulting heat over more tread works better.

Modern sports cars use wider tires because their cornering traction is superior to that of narrower tires. Not sure why.

Assuming the same rubber compound, a wider tire would probably last longer than a narrower tire because the same tread is in contact with the road for less time as the tire rotates. This could be one reason that i3 tires tend to wear faster than other tires.

 

[Lesterbmwi3]

I notice better mileage on ecopia than blizzak my driving in NY is 2000 on ecopia and 1000 miles on blizzak obviously i m driving about 3000 miles a year I’m using this car as an go cart driving around in Staten Island NY and Iove it is 2014 only 14000 miles so far no problems my concern is when my 12V battery going to dye 5years. Old bc you stack without 12Vpower any input about 12Vbattery how you people dealing with ?Thanks if you have any problems to share ?

 

[Lesterbmwi3]

Is only car with 5” tires and I pass all BMW 3 series with 7/8 width tires why you need bigger tires I’m playing with guys on o road with Gus guslers bmw’s you faster in 60 miles range than all 90% cars on a road what wider tires help you with? You have to learn how to take advantage of low gravity car and direct torck Ex racer car driver

 

[Lesterbmwi3]

Your wider tires don’t make race car spend $ 250000 on electric car and you have a race car be happy you own Bmw I 3 is a faster car on a street in small package/ Race car driver /and know the 2014 BMW I 3 with 60 amp hr battery is the fastest go card on the road!!!!!!! The first production of Bmw

 

[benrk]

As I’m just about to ship an i3 to an area where they are not very common & I can pretty much expect no one in the area to cary stock in tires for the foreseeable future, has anyone ever researched compatible „donut“ spare tire sizes? Iirc the i3 has 5 & 112 bolt pattern, is there a chance to find something compatible at a wrecker from an MB ML/GL?

Thx, Ben

 

[AndrewDebbie]

Nobody around here stocks i3s tyres. We have to order them from Germany.

 

[jadnashuanh]

Nobody around here stocks i3s tyres. We have to order them from Germany.

That may sound like a pain, but it's shorter distance than across the US, and much further than from Germany. STill, in air freight across the pond, it's still only a day. Much longer by boat. In your case, even a freight train is probably not much more than a day.

 

[AndrewDebbie]

Delivery is about 3 days. It probably goes on a truck via the Eurotunel but there are other routes. Some people on the UK i3 FB group keep extras on hand. Others have a winter set they can put back on while waiting. For the i3s that means getting winter wheels too.

I'm American. I've lived in the UK about 10 years. When I lived in the US, I had tyres air shipped from England. It wasn't too expensive. I was surprised. Of course you need to find a seller willing to go through effort.


It is convenient that we can order things from Germany and have them here a few days. Many even have websites in English. No hassles with import duty or customs brokerage fees. I've got an genuine BMW i3 dog guard on the way from Germany. Fingers crossed that Brexit doesn't ruin this for us.




Off-topic but we get small package rail-mail all the way from China. S l o w but is very inexpensive.

 

[joeguzman10]

Any thoughts on using tires listed below?

BMW i3 Tires & Conversion [Size Diameter Width] inches

Front 155/70R19 27.56 6.10
Rear 175/60R19 27.28 6.89


Compatibale Tires [Size Diameter Width] inches
F&R 195/65R16 25.98 7.68

F&R 205/55R17  25.87 8.07

F&R 225/55R18 27.76 8.86

F&R 225/55R19 28.74 8.86

 

[WileE]

Just a note on tread life......
All electrics burn thru tyres faster, including Teslas. Electrics have torque and that's equals abuse on your tyres even when going lite on the juice. Was on test drive for a model 3 few months back and sales rep laughed when I asked if it would get better miles than my i3. Was told to never expect more than 15-18k miles or 28980km from a set. Incidentally, I chose to go with another i3

 

[ted99]

The upcoming Mini Electric is reported to use the complete i3 drivetrain, except it's to be FWD, rather than RWD. It'll be interesting to see if it's wheels will bolt up to the i3 hubs. I suspect that they will if it's the same drivetrain, but offsets may be a problem. Looking forward to what the wheel/tire combo is for the Mini Electric and whether it's an improvement over the i3's tires. I'd really like to see a more "normal" set of sizes so that we would have a choice in tires.

 

[Boxbrownie]

The upcoming Mini Electric is reported to use the complete i3 drivetrain, except it's to be FWD, rather than RWD. It'll be interesting to see if it's wheels will bolt up to the i3 hubs. I suspect that they will if it's the same drivetrain, but offsets may be a problem. Looking forward to what the wheel/tire combo is for the Mini Electric and whether it's an improvement over the i3's tires. I'd really like to see a more "normal" set of sizes so that we would have a choice in tires.

Very much doubt that, as the Mini will be front wheel drive it will use completely different hubs than the i3 (most likely normal Mini hubs) and looking at the Mini EV early pictures the wheels are not the “tall and very narrow” type that the i3 uses.

As for sourcing i3 tyres, I needed a new set recently and two local independent tyre dealers had them in stock at their warehouse (next day delivery and fitting) and my local BMW dealer also had them in stock and would price match the tyres dealers, no contest then.

 

[vreihen]

Stupid question - Did BMW really use a different hub size on the i3 and Mini? Both appear to be using 5x112 bolt patterns from a quick web search that I did. I assume that they are both hub-centric, so the only reason why they couldn't be crossed over (wheel offsets and rubbing aside) would be that the center hub were different sizes between the two. The 2015+ Mini appears to even be using the same hub diameter and lug bolts, hence why I'm scratching my head.....

 

[Anonymous]

I assume that they are both hub-centric, so the only reason why they couldn't be crossed over (wheel offsets and rubbing aside) would be that the center hub were different sizes between the two.

Both the Mini Cooper and the BMW i3, have the same hub size. The hub center bore is 66.6 mm for both.

As you noted, the difference comes in the offset. the i3 wheel has a positive offset of 43 mm front and 53 mm rear , and 33/39 mm for the i3S - and size of wheel.

The Mini Cooper shows an offset of anywhere from 46 mm to 54 mm depending on the wheel size ( 14" to 18")

Not sure I'd want to try the smaller Mini Cooper wheel on a car that OEM's a 19 though, you'd get that 'Ricer' look, and you'd be dragging the battery pack on the pavement every time you hit a bump. :mrgreen:

This site will allow you to see and compare specs.

https://www.wheel-size.com/