Why don't BMW new energy vehicles use run-flat tires?

[ChloeDella]

Run-flat tires are much heavier than regular tires, adding dozens of kilograms across four tires. Electric vehicles generally don't come with spare tires, partly due to geometric matching issues but also for weight reduction. Here's relevant information: 1. Function of run-flat tires: Run-flat tires primarily rely on thickened rubber sidewalls that can support the vehicle's weight even when the tire loses pressure. If the BMW 5 Series new energy model had run-flat tires, even a blowout wouldn't cause severe tire deformation that would significantly affect its driving. 2. Vehicle stability control: This is a braking system that prevents skidding under emergency driving conditions. If the BMW 5 Series new energy model is equipped with a vehicle stability control system, it can maintain optimal stability in various situations and help preserve dynamic balance.

[LeFinley]

I've always been very interested in this issue, especially after driving several electric vehicles. BMW's new energy models like the i-series don't use run-flat tires mainly due to weight concerns. New energy vehicles already have heavy batteries, and run-flat tires add even more weight, increasing the overall burden and affecting both range and acceleration performance. Additionally, new energy vehicle designs emphasize efficiency and energy savings, and run-flat tires have higher rolling resistance, which can reduce battery efficiency and shorten driving distance. BMW likely opted for conventional tires to optimize overall efficiency. I've also noticed that run-flat tires offer poorer comfort and generate more noise, which can disrupt the driving experience in electric vehicles that emphasize quietness. As an owner, if you encounter a flat tire, the i3 usually comes equipped with a tire repair kit or roadside assistance service, ensuring safety isn't compromised—a topic frequently discussed in community forums and quite practical.

[MarianaLee]

When driving BMW's new energy vehicles, I noticed the issue of tire comfort. Although run-flat tires are puncture-resistant, their material is too hard, causing noticeable vibrations when going over speed bumps or rough roads, which negatively affects the quiet environment of electric vehicles. BMW likely opted not to use them to enhance the smoothness of daily driving. Moreover, the battery accounts for the majority of the weight in new energy vehicles, and run-flat tires would only make the car heavier, compromising handling agility and range. Considering the anxiety before each charge, lighter tires offer an advantage. From a cost perspective, run-flat tires are expensive, and switching to regular tires lowers the entry barrier and maintenance costs, which is quite cost-effective for budget-conscious users like me. The air pump toolkit provided by BMW also offers convenient emergency handling, making it easy to use without worries.

[AlessandraMarie]

From a market strategy perspective, BMW's decision not to equip all its new energy vehicles with run-flat tires is a result of careful trade-offs. Run-flat tires are costly, which drives up vehicle prices, and in the highly competitive new energy market, a lower price point is more attractive to buyers. Range is a critical factor, and run-flat tires add weight and resistance, which can reduce actual mileage. BMW has prioritized efficient tires to enhance battery performance. User feedback also indicates that regular tires are easier to maintain and repair shops are more readily available, unlike run-flat tires, which are more complex to replace—a practical advantage for long-distance travel. BMW's design team likely believes that the combination of an onboard tool kit and 24-hour roadside assistance provides sufficient safety, offering a cost-effective and practical solution that aligns with modern trends.