Originally Posted By: fdcg27
Why are run-flats even used?
The one series BMW is not particularly efficient in either weight or space utilization and the premium paid to mount OEM run-flats over the cost of the middling performance tires that would otherwise be used, a jack, a lug wrench and a donut can't be saving much money for BMW.
I don't think it's about saving money at the time of vehicle build. It's about saving space and saving weight. Some versions of the Chevy Cruze use run-flat tires as well, and I believe the reason is the weight savings over carrying around a jack and a fifth tire. Most modern Corvettes use run-flat tires, at least from the factory. My brother's 1999 C5 is one such example.
I'm with you on the compromises. I'd make the compromise by carrying a jack and a fifth tire around all the time. But those are the reasons nonetheless.
Why are run-flats even used?
The one series BMW is not particularly efficient in either weight or space utilization and the premium paid to mount OEM run-flats over the cost of the middling performance tires that would otherwise be used, a jack, a lug wrench and a donut can't be saving much money for BMW.
I don't think it's about saving money at the time of vehicle build. It's about saving space and saving weight. Some versions of the Chevy Cruze use run-flat tires as well, and I believe the reason is the weight savings over carrying around a jack and a fifth tire. Most modern Corvettes use run-flat tires, at least from the factory. My brother's 1999 C5 is one such example.
I'm with you on the compromises. I'd make the compromise by carrying a jack and a fifth tire around all the time. But those are the reasons nonetheless.